{"id":196,"date":"2023-05-22T10:52:26","date_gmt":"2023-05-22T02:52:26","guid":{"rendered":"https:\/\/www.escook.cn\/?p=196"},"modified":"2023-09-26T21:07:14","modified_gmt":"2023-09-26T13:07:14","slug":"dart-%e5%9f%ba%e7%a1%80-%e5%86%85%e7%bd%ae%e7%b1%bb%e5%9e%8b-list-%e9%9b%86%e5%90%88","status":"publish","type":"post","link":"https:\/\/www.escook.cn\/index.php\/2023\/05\/22\/dart-%e5%9f%ba%e7%a1%80-%e5%86%85%e7%bd%ae%e7%b1%bb%e5%9e%8b-list-%e9%9b%86%e5%90%88\/","title":{"rendered":"Dart \u57fa\u7840 – \u5185\u7f6e\u7c7b\u578b – List \u96c6\u5408"},"content":{"rendered":"
\n

\u7248\u6743\u5f52\u4f5c\u8005 \u00a9\u5218\u9f99\u5bbe<\/strong> \u6240\u6709\uff0c\u672c\u6587\u7ae0\u672a\u7ecf\u4f5c\u8005\u5141\u8bb8\uff0c\u7981\u6b62\u79c1\u81ea\u8f6c\u8f7d\uff01<\/p>\n<\/blockquote>\n

\u5728 Dart \u7684\u5185\u7f6e\u7c7b\u578b\u4e2d\uff0c\u96c6\u5408\u76f8\u5173\u7684\u7c7b\u578b\u5171\u67093\u4e2a\uff0c\u5206\u522b\u662f\uff1a<\/p>\n

    \n
  1. List<\/li>\n
  2. Set<\/li>\n
  3. Map<\/li>\n<\/ol>\n

    \u5176\u4e2d List \u96c6\u5408<\/strong>\u5c31\u662f\u5176\u5b83\u8bed\u8a00\u4e2d\u6240\u8c13\u7684\u6570\u7ec4<\/strong>\uff08Array\uff09\uff0c\u5728 Dart \u4e2d\u6570\u7ec4\u7528 List<\/a> \u5bf9\u8c61\u8868\u793a\uff0c\u672c\u8282\u4e3b\u8981\u8ba8\u8bba\u5b83\u7684\u57fa\u672c\u4f7f\u7528\u3002<\/p>\n

    1. \u58f0\u660e List \u6570\u7ec4<\/h2>\n

    1.1 \u57fa\u4e8e\u5b57\u9762\u91cf\u521b\u5efa List<\/h3>\n

    1.1.1 \u5b8c\u6574\u5f62\u5f0f<\/h4>\n

    \u57fa\u4e8e\u5b57\u9762\u91cf<\/strong> <\u7c7b\u578b>[]<\/code> \u662f\u521b\u5efa List \u6570\u7ec4\u6700\u7b80\u5355\u7684\u65b9\u5f0f\u3002\u4f8b\u5982\uff0c\u4e0b\u9762\u7684\u4ee3\u7801\u521b\u5efa\u4e86\u4e00\u4e2a\u7a7a\u6570\u7ec4 arr<\/code>\uff0c\u7528\u6765\u5b58\u50a8 int<\/code> \u7c7b\u578b\u7684\u5143\u7d20\uff1a<\/p>\n

    void main(List<String> args) {\n  \/\/ 1. \u53f3\u4fa7\u7684 <int> \u7528\u6765\u6307\u5b9a [] \u4e2d\u5b58\u50a8\u7684\u5143\u7d20\u7684\u6570\u636e\u7c7b\u578b\u5fc5\u987b\u662f int \u6570\u5b57\n  \/\/ 2. \u5de6\u4fa7\u7684 List<int> \u8868\u793a arr \u53d8\u91cf\u7684\u7c7b\u578b\u662f List \u6570\u7ec4\uff0c\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u7c7b\u578b\u662f int\n  List<int> arr = <int>[];\n\n  \/\/ 3. length \u5c5e\u6027\u7528\u6765\u67e5\u770b\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u4e2a\u6570\n  print(arr.length); \/\/ \u8f93\u51fa 0\n  \/\/ 4. isEmpty \u5c5e\u6027\u7528\u6765\u5224\u65ad\u6570\u7ec4\u662f\u5426\u4e3a\u7a7a\n  print(arr.isEmpty); \/\/ \u8f93\u51fa true\n}<\/code><\/pre>\n
    1.1.2 \u7c7b\u578b\u7b80\u5199<\/h4>\n
    List<int> arr = <int>[];<\/code> \u662f\u57fa\u4e8e\u5b57\u9762\u91cf\u521b\u5efa\u6570\u7ec4\u7684\u5b8c\u6574\u5f62\u5f0f<\/strong>\u3002\u5176\u4e2d\uff0c\u53f3\u4fa7\u7684 <int><\/code> \u548c\u5de6\u4fa7\u7684 List<int><\/code> \u90fd\u6307\u5b9a\u4e86\u6570\u7ec4\u5143\u7d20\u7684\u7c7b\u578b\uff0c\u5728\u5199\u6cd5\u4e0a\u6709\u4e9b\u5197\u4f59\u3002\u6211\u4eec\u53ef\u4ee5\u6309\u9700\u7701\u7565\u5de6\u4fa7<\/strong>\u6216\u53f3\u4fa7<\/strong>\u7684\u7c7b\u578b\uff0c\u4f9d\u7136\u80fd\u4fdd\u8bc1 arr<\/code> \u662f int<\/code> \u7c7b\u578b\u7684\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ List<int> arr = <int>[]; \/\/ \u5b8c\u6574\u5199\u6cd5\uff0c\u5de6\u4fa7\u548c\u53f3\u4fa7\u90fd\u5305\u542b\u7c7b\u578b\u58f0\u660e\n  \/\/ var arr = <int>[];  \/\/ \u628a\u5de6\u8fb9\u7684\u7c7b\u578b\u7701\u7565\uff0c\u53f3\u4fa7\u7684 <int> \u8868\u793a arr \u662f int \u7c7b\u578b\u7684\u6570\u7ec4\n  \/\/ List<int> arr = []; \/\/ \u628a\u53f3\u8fb9\u7684\u7c7b\u578b\u7701\u7565\uff0c\u5de6\u4fa7\u7684 List<int> \u8868\u793a arr \u662f int \u7c7b\u578b\u7684\u6570\u7ec4\n}<\/code><\/pre>\n
    \u4e0a\u9762\u7684\u4ee3\u7801\u7b80\u5316\u4e86\u5b9a\u4e49\u6570\u7ec4\u65f6\u7684\u7c7b\u578b\u58f0\u660e\uff0c\u4ee3\u7801\u66f4\u4e3a\u7b80\u6d01\uff0c\u540c\u65f6\u8fd8\u80fd\u4fdd\u8bc1\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u7c7b\u578b\uff0c\u4f8b\u5982\u5411 int \u6570\u7ec4\u4e2d\u6dfb\u52a0\u5176\u5b83\u7c7b\u578b\u7684\u5143\u7d20\u65f6\uff0c\u4ee3\u7801\u4f1a\u62a5\u9519\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u58f0\u660e int \u7c7b\u578b\u7684\u6570\u7ec4 arr\n  var arr = <int>[];\n\n  \/\/ 2. \u8c03\u7528\u6570\u7ec4\u7684 add() \u65b9\u6cd5\uff0c\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\n  \/\/ int \u7c7b\u578b\u7684\u6570\u5b57 1 \u53ef\u4ee5\u6b63\u5e38\u7684\u6dfb\u52a0\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u56e0\u4e3a\u5143\u7d20\u7684\u7c7b\u578b\u548c\u6570\u7ec4\u7684\u7c7b\u578b\u5339\u914d\n  arr.add(1);\n  \/\/ 3. \u5b57\u7b26\u4e32 'abc' \u65e0\u6cd5\u88ab\u6dfb\u52a0\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u56e0\u4e3a\u7c7b\u578b\u4e0d\u5339\u914d\uff0c\u6240\u4ee5\u4e0b\u9762\u8fd9\u884c\u4ee3\u7801\u7f16\u8bd1\u4f1a\u62a5\u9519\n  arr.add('abc');\n}<\/code><\/pre>\n
    1.1.3 dynamic \u6570\u7ec4<\/h4>\n
    \u6ce8\u610f\uff0c\u5982\u679c\u540c\u65f6\u7701\u7565\u4e86\u5de6\u4fa7\u548c\u53f3\u4fa7\u7684\u7c7b\u578b\uff0c\u5219\u8868\u793a\u58f0\u660e\u4e86\u4e00\u4e2a dynamic<\/code> \u7c7b\u578b\u7684\u6570\u7ec4\u3002\u6b64\u65f6\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4e0d\u540c\u7c7b\u578b\u7684\u5143\u7d20\uff0c\u76f8\u5f53\u4e8e\u89e3\u9664\u4e86\u6570\u7ec4\u4e2d\u5143\u7d20\u7c7b\u578b\u5fc5\u987b\u4e00\u81f4\u7684\u9650\u5236<\/strong>\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b8c\u6574\u5199\u6cd5\uff0c\u5de6\u4fa7\u548c\u53f3\u4fa7\u90fd\u5305\u542b\u7c7b\u578b\u58f0\u660e\uff0c\u628a arr \u9650\u5b9a\u4e3a\u4e86 int \u7c7b\u578b\u7684\u6570\u7ec4\n  \/\/ List<int> arr = <int>[];\n\n  \/\/ 2. \u540c\u65f6\u7701\u7565\u4e24\u8fb9\u7684\u7c7b\u578b\uff0c\u8868\u793a\u58f0\u660e\u4e86 dynamic \u52a8\u6001\u7c7b\u578b\u7684\u6570\u7ec4\uff0c\n  \/\/ \u7b49\u540c\u4e8e\u5b8c\u6574\u5199\u6cd5\u7684\u58f0\u660e\u65b9\u5f0f\uff1a List<dynamic> arr = <dynamic>[];\n  \/\/ \u6b64\u65f6\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u5b58\u50a8\u4efb\u610f\u7c7b\u578b\u7684\u5143\u7d20\n  var arr = [];\n\n  \/\/ 3.1 \u6dfb\u52a0\u6570\u5b57 1\n  arr.add(1);\n  \/\/ 3.2 \u6dfb\u52a0\u5b57\u7b26\u4e32 'abc'\n  arr.add('abc');\n  \/\/ 3.3 \u6dfb\u52a0\u5e03\u5c14\u503c true\n  arr.add(true);\n\n  \/\/ 4. \u8f93\u51fa [1, abc, true]\n  print(arr);\n}<\/code><\/pre>\n
    1.1.4 \u5e38\u91cf\u6570\u7ec4<\/h4>\n
    \u5728 Dart \u4e2d\uff0c\u53ef\u4ee5\u57fa\u4e8e const<\/code> \u58f0\u660e\u7f16\u8bd1\u65f6\u7684\u5e38\u91cf\u6570\u7ec4<\/strong>\u3002\u4f7f\u7528 const <\/code> \u58f0\u660e\u7684\u6570\u7ec4\u662f unmodifiable<\/code> \u7684 List\uff0c\u5373 \u201c\u4e0d\u53ef\u4fee\u6539<\/strong>\u201d\u7684\u6570\u7ec4\u3002\u65e0\u6cd5\u5220\u9664\u5143\u7d20\u3001\u4fee\u6539\u5143\u7d20\u3001\u6269\u5145\u6570\u7ec4\u957f\u5ea6\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u53ef\u53d8\u6570\u7ec4 counts\n  List<int?> counts = [1, 2, 3];\n\n  \/\/ 1.1 \u53ef\u4ee5\u4fee\u6539\u5143\u7d20\n  counts[0] = 9;\n  print(counts); \/\/ \u8f93\u51fa [9, 2, 3]\n\n  \/\/ 1.2 \u53ef\u4ee5\u6269\u5145\u6570\u7ec4\uff08\u65b0\u6269\u5145\u7684\u5143\u7d20\u9ed8\u8ba4\u503c\u4e3a null\uff0c\u56e0\u6b64\u8981\u628a\u6570\u7ec4\u7c7b\u578b\u5b9a\u4e49\u6210\u53ef\u4e3a\u7a7a\u7684 List\uff0c\u5373 List<int?> \u7c7b\u578b\uff09\n  counts.length = 5;\n  print(counts); \/\/ \u8f93\u51fa [9, 2, 3, null, null]\n\n  \/\/ 1.3 \u53ef\u4ee5\u5220\u9664\u5143\u7d20\n  counts.removeAt(0);\n  print(counts); \/\/ \u8f93\u51fa [2, 3, null, null]\n\n  \/\/ ----\n\n  \/\/ 2. \u5b9a\u4e49\u5e38\u91cf\u6570\u7ec4 ages\uff0c\u4e0b\u9762\u7684\u4ee3\u7801\u7b49\u540c\u4e8e const List<int> ages = [22, 28, 19];\n  List<int> ages = const [22, 28, 19];\n\n  \/\/ 2.1 \u4fee\u6539\u5143\u7d20\u7684\u503c\uff0c\u62a5\u9519\uff1aCannot modify an unmodifiable list\n  ages[0] = 31;\n\n  \/\/ 2.2 \u6269\u5145\u6570\u7ec4\uff0c\u62a5\u9519\uff1aCannot change the length of an unmodifiable list\n  ages.length = 5;\n\n  \/\/ 2.3 \u5220\u9664\u5143\u7d20\uff0c\u62a5\u9519\uff1aCannot remove from an unmodifiable list\n  ages.removeAt(0);\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u5728\u5b9a\u4e49\u5e38\u91cf\u6570\u7ec4\u65f6\uff0c\u5173\u952e\u5b57 const \u53ef\u4ee5\u653e\u5728\u5b57\u9762\u91cf\u6570\u7ec4\u4e4b\u524d\uff0c\u4e5f\u53ef\u4ee5\u653e\u5728\u53d8\u91cf\u7c7b\u578b\u4e4b\u524d\uff0c\u4ee5\u4e0b\u4ee3\u7801\u662f\u7b49\u4ef7\u7684\uff1a
    \nconst List ages = [1, 2, 3];
    \nList ages = const [1, 2, 3];<\/p>\n<\/blockquote>\n
    1.2 \u57fa\u4e8e\u6784\u9020\u51fd\u6570\u521b\u5efa List<\/h3>\n
    1.2.1 List.empty()<\/h4>\n
    \u57fa\u4e8e List.empty({bool growable = false});<\/code> \u6784\u9020\u51fd\u6570\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2a\u7a7a\u6570\u7ec4\u3002\u5176\u4e2d\u53ef\u9009\u53c2\u6570 growable<\/code> \u7684\u9ed8\u8ba4\u503c\u4e3a false<\/code>\uff0c\u8868\u793a\u521b\u5efa\u7684\u7a7a\u6570\u7ec4\u957f\u5ea6\u56fa\u5b9a\u4e3a 0\uff0c\u4e0d\u5141\u8bb8\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u65b0\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u57fa\u4e8e empty \u6784\u9020\u51fd\u6570\uff0c\u521b\u5efa\u7a7a\u6570\u7ec4\uff0c\n  \/\/ growable \u7684\u9ed8\u8ba4\u503c\u4e3a false\uff0c\u8868\u793a\u7a7a\u6570\u7ec4\u7684\u957f\u5ea6\u56fa\u5b9a\u4e3a 0\uff0c\u4e0d\u5141\u8bb8\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20\n  List arr1 = List.empty();\n\n  print(arr1.length); \/\/ \u8f93\u51fa 0\n\n  \/\/ \u62a5\u9519 Cannot add to a fixed-length list\n  \/\/ \u65e0\u6cd5\u5411\u56fa\u5b9a\u957f\u5ea6\u7684\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\n  arr1.add(1);\n}<\/code><\/pre>\n
    \u4e3a\u4e86\u521b\u5efa\u53ef\u589e\u957f\u7684\u7a7a\u6570\u7ec4\uff0c\u53ef\u4ee5\u5728\u8c03\u7528 empty()<\/code> \u6784\u9020\u51fd\u6570\u65f6\u628a growable<\/code> \u9009\u9879\u8bbe\u7f6e\u4e3a true<\/code>\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u628a growable \u8bbe\u7f6e\u4e3a true\n  List arr1 = List.empty(growable: true);\n  print(arr1.length); \/\/ \u8f93\u51fa 0\n\n  \/\/ \u53ef\u4ee5\u6b63\u5e38\u6dfb\u52a0\u5143\u7d20\n  arr1.add('abc');\n\n  print(arr1); \/\/ \u8f93\u51fa [abc]\n  print(arr1.length); \/\/ \u8f93\u51fa 1\n}<\/code><\/pre>\n
    1.2.2 List.filled()<\/h4>\n
    \u57fa\u4e8e List.filled(int length, E fill, {bool growable = false});<\/code> \u6784\u9020\u51fd\u6570\uff0c\u53ef\u4ee5\u521b\u5efa\u6307\u5b9a\u957f\u5ea6\u7684\u6570\u7ec4<\/strong>\uff0c\u5e76\u4ee5\u7ed9\u5b9a\u7684\u5185\u5bb9<\/strong>\u4f5c\u4e3a\u6bcf\u4e2a\u5143\u7d20\u7684\u521d\u503c<\/strong>\u8fdb\u884c\u586b\u5145\u3002\u5176\u4e2d\u7b2c\u4e09\u4e2a\u53c2\u6570 growable <\/code> \u7684\u9ed8\u8ba4\u503c\u4e3a false<\/code>\uff0c\u8868\u793a\u521b\u5efa\u7684\u662f\u957f\u5ea6\u56fa\u5b9a\u7684\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u521b\u5efa\u957f\u5ea6\u4e3a 3 \u7684\u6570\u7ec4\uff0c\u5e76\u628a\u6bcf\u4e2a\u5143\u7d20\u7684\u521d\u59cb\u503c\u586b\u5145\u4e3a\u6570\u5b57 0\n  List<int> arr2 = List.filled(3, 0);\n  \/\/ \u8f93\u51fa [0, 0, 0]\n  print(arr2);\n\n  \/\/ \u628a\u7d22\u5f15\u4e3a 0 \u7684\u5143\u7d20\u8d4b\u503c\u4e3a 9\n  \/\/ \u6ce8\u610f\uff1a\u56fa\u5b9a\u957f\u5ea6\u7684\u6570\u7ec4\u6307\u5143\u7d20\u7684\u4e2a\u6570\u4e0d\u80fd\u589e\u52a0\u4e5f\u4e0d\u80fd\u51cf\u5c11\uff0c\u4f46\u662f\u4e0d\u5f71\u54cd\u4fee\u6539\u73b0\u6709\u5143\u7d20\u7684\u503c\n  arr2[0] = 9;\n  \/\/ \u8f93\u51fa [9, 0, 0]\n  print(arr2);\n\n  \/\/ \u62a5\u9519 Cannot add to a fixed-length list\n  \/\/ \u65e0\u6cd5\u5411\u56fa\u5b9a\u957f\u5ea6\u7684\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\n  \/\/ arr2.add(9);\n\n  \/\/ \u62a5\u9519 Cannot change the length of a fixed-length list\n  \/\/ \u65e0\u6cd5\u4fee\u6539\u56fa\u5b9a\u957f\u5ea6\u7684\u6570\u7ec4\u7684 length\n  \/\/ arr2.length = 1;\n}<\/code><\/pre>\n
    \u53ef\u4ee5\u663e\u793a\u6307\u5b9a growable <\/code> \u4e3a true<\/code> \u4ece\u800c\u521b\u5efa\u53ef\u589e\u957f\u7684\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u521b\u5efa\u521d\u59cb\u957f\u5ea6\u4e3a 3 \u7684\u6570\u7ec4\uff0c\u5e76\u628a\u6bcf\u4e2a\u5143\u7d20\u7684\u521d\u59cb\u503c\u586b\u5145\u4e3a\u6570\u5b57 0\n  List<int?> arr2 = List.filled(3, 0, growable: true);\n  \/\/ \u8f93\u51fa [0, 0, 0]\n  print(arr2);\n\n  \/\/ \u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 9\n  arr2.add(9);\n  \/\/ \u8f93\u51fa [0, 0, 0, 9]\n  print(arr2);\n\n  \/\/ \u4fee\u6539\u6570\u7ec4\u7684 length \u4e3a 1\uff0c\u4f1a\u5220\u9664\u591a\u4f59\u7684\u5143\u7d20\n  arr2.length = 1;\n  \/\/ \u8f93\u51fa [0]\n  print(arr2);\n\n  \/\/ \u6269\u5145\u6570\u7ec4\u7684 length \u4e3a 5\uff0c\u65b0\u6269\u5145\u7684\u5143\u7d20\u503c\u4f1a\u88ab\u586b\u5145\u4e3a null\n  \/\/ \u6ce8\u610f\uff1a\u58f0\u660e\u6570\u7ec4\u65f6\u5fc5\u987b\u4f7f\u7528 List<int?> \u628a\u6570\u7ec4\u5143\u7d20\u58f0\u660e\u6210\u53ef\u4e3a null \u7684\u5143\u7d20\uff0c\u5426\u5219\u6269\u5145\u4f1a\u62a5\u9519\n  arr2.length = 5;\n  \/\/ \u8f93\u51fa [0, null, null, null, null]\n  print(arr2);\n}<\/code><\/pre>\n
    1.2.3 List.unmodifiable()<\/h4>\n
    \u57fa\u4e8e List.unmodifiable(Iterable elements);<\/code> \u6784\u9020\u51fd\u6570\uff0c\u53ef\u4ee5\u521b\u5efa\u4e0d\u53ef\u4fee\u6539<\/strong>\u7684\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u666e\u901a\u6570\u7ec4\n  var arr1 = <int>[1, 2, 3];\n  \/\/ 3. \u8c03\u7528 unmodifiable \u6784\u9020\u51fd\u6570\uff0c\u57fa\u4e8e arr1 \u521b\u5efa\u51fa\u4e0d\u53ef\u4fee\u6539\u7684\u6570\u7ec4 arr2\n  var arr2 = List.unmodifiable(arr1);\n\n  \/\/ 3. \u62a5\u9519 Cannot change the length of an unmodifiable list\n  \/\/ \u4e0d\u5141\u8bb8\u4fee\u6539\u6570\u7ec4\u7684 length\n  \/\/ arr2.length = 1;\n\n  \/\/ 4. \u62a5\u9519 Cannot modify an unmodifiable list\n  \/\/ \u4e0d\u5141\u8bb8\u4fee\u6539\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u503c\n  \/\/ arr2[0] = 9;\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1agrowable \u4e3a false \u7684\u6570\u7ec4\uff0c\u4e0d\u5141\u8bb8\u6dfb\u52a0\u548c\u5220\u9664\u5143\u7d20\uff0c\u4f46\u662f\u5141\u8bb8\u4fee\u6539\u73b0\u6709\u5143\u7d20\u7684\u503c\u3002\u800c unmodifiable \u7684\u6570\u7ec4\u65e2\u4e0d\u5141\u8bb8\u6dfb\u52a0\u548c\u5220\u9664\u5143\u7d20\uff0c\u53c8\u4e0d\u5141\u8bb8\u4fee\u6539\u73b0\u6709\u5143\u7d20\u7684\u503c\u3002<\/p>\n<\/blockquote>\n
    2. \u64cd\u4f5c List \u5143\u7d20<\/h2>\n
    2.1 \u6dfb\u52a0\u5143\u7d20<\/h3>\n
    2.1.1 \u6dfb\u52a0\u5355\u4e2a\u5143\u7d20<\/h4>\n
    \u8c03\u7528\u6570\u7ec4\u7684 add<\/code> \u65b9\u6cd5\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5355\u4e2a\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u5b9a\u4e49\u6570\u7ec4\uff08\u53ef\u589e\u957f\uff09\n  List<String> names = [];\n\n  \/\/ add \u65b9\u6cd5\u4e00\u6b21\u53ea\u80fd\u6dfb\u52a0 1 \u4e2a\u5143\u7d20\n  names.add('zs');\n  names.add('ls');\n\n  \/\/ \u8f93\u51fa [zs, ls]\n  print(names);\n}<\/code><\/pre>\n
    2.1.2 \u6dfb\u52a0\u591a\u4e2a\u5143\u7d20<\/h4>\n
    \u8c03\u7528\u6570\u7ec4\u7684 addAll<\/code> \u65b9\u6cd5\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u4e00\u6b21\u6027\u6dfb\u52a0\u591a\u4e2a\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u5b9a\u4e49\u6570\u7ec4\n  List<int> arr = [1, 2];\n  \/\/ \u4e00\u6b21\u6027\u6dfb\u52a0\u591a\u4e2a\u5143\u7d20\n  arr.addAll([3, 4, 5]);\n  \/\/ \u8f93\u51fa [1, 2, 3, 4, 5]\n  print(arr);\n}<\/code><\/pre>\n
    2.2 \u79fb\u9664\u5143\u7d20<\/h3>\n
    2.2.1 remove()<\/h4>\n
    \u6570\u7ec4\u7684 remove<\/code> \u65b9\u6cd5\u7528\u6765\u79fb\u9664\u6307\u5b9a\u7684\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = ['A', 'B', 'C', 'D', 'E', 'F', 'A'];\n  \/\/ \u79fb\u9664\u6307\u5b9a\u7684\u5143\u7d20\uff0c\u5982\u679c\u79fb\u9664\u6210\u529f\uff0c\u5219\u8fd4\u56de true\uff0c\u5426\u5219\u8fd4\u56de\u5931\u8d25\n  \/\/ \u5982\u679c\u5b58\u5728\u591a\u4e2a\u76f8\u540c\u7684\u5143\u7d20\uff0c\u5219\u53ea\u79fb\u9664\u6700\u5de6\u4fa7\u7684\u90a3\u4e2a\u5143\u7d20\n  bool result = arr.remove('A');\n\n  print(result); \/\/ \u8f93\u51fa true\n  print(arr); \/\/ \u8f93\u51fa [B, C, D, E, F, A]\n\n  bool result2 = arr.remove('Z');\n  print(result2); \/\/ \u8f93\u51fa false\uff0c\u56e0\u4e3a\u6570\u7ec4\u4e2d\u4e0d\u5b58\u5728\u5143\u7d20 'Z'\n}<\/code><\/pre>\n
    2.2.2 removeLast()<\/h4>\n
    \u6570\u7ec4\u7684 removeLast<\/code> \u65b9\u6cd5\u7528\u6765\u4ece\u672b\u5c3e\u79fb\u9664\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = ['A', 'B', 'C', 'D', 'E', 'F'];\n  \/\/ \u79fb\u9664\u6570\u7ec4\u672b\u5c3e\u7684\u5143\u7d20\uff0c\u5e76\u8fd4\u56de\u8fd9\u4e2a\u88ab\u79fb\u9664\u7684\u5143\u7d20\n  var result = arr.removeLast();\n\n  print(result); \/\/ \u8f93\u51fa F\n  print(arr); \/\/ \u8f93\u51fa [A, B, C, D, E]\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u5728\u7a7a\u6570\u7ec4\u4e0a\u8c03\u7528 removeLast \u65b9\u6cd5\u4f1a\u62a5\u9519\u3002<\/p>\n<\/blockquote>\n
    2.2.3 removeAt()<\/h4>\n
    \u6570\u7ec4\u7684 removeAt<\/code> \u65b9\u6cd5\u7528\u6765\u6839\u636e\u7d22\u5f15\u79fb\u9664\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = ['A', 'B', 'C', 'D', 'E', 'F'];\n  \/\/ \u79fb\u9664\u6307\u5b9a\u7d22\u5f15\u7684\u5143\u7d20\uff0c\u5e76\u8fd4\u56de\u8fd9\u4e2a\u88ab\u79fb\u9664\u7684\u5143\u7d20\n  var result = arr.removeAt(1);\n\n  print(result); \/\/ \u8f93\u51fa B\n  print(arr); \/\/ \u8f93\u51fa [A, C, D, E, F]\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u5982\u679c\u63d0\u4f9b\u7684\u7d22\u5f15\u5c0f\u4e8e 0 \u6216\u5927\u4e8e length-1\uff0c\u5219\u4f1a\u62a5\u9519\u3002<\/p>\n<\/blockquote>\n
    2.2.4 removeRange()<\/h4>\n
    \u6570\u7ec4\u7684 removeRange(int start, int end)<\/code> \u65b9\u6cd5\u7528\u6765\u6839\u636e\u7d22\u5f15\u8303\u56f4\u79fb\u9664\u533a\u95f4\u5185\u7684\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = ['A', 'B', 'C', 'D', 'E', 'F'];\n  \/\/ \u6839\u636e\u8d77\u59cb\u7d22\u5f15\u548c\u7ed3\u675f\u7d22\u5f15\uff0c\u79fb\u9664\u8303\u56f4\u5185\u7684\u5143\u7d20\n  \/\/ \u6ce8\u610f\uff1a\u5305\u524d\u4e0d\u5305\u540e\uff0c\u79fb\u9664\u7684\u8303\u56f4\u662f\u7d22\u5f15\u4e3a start \u5230\u7d22\u5f15\u4e3a end-1 \u7684\u5143\u7d20\n  arr.removeRange(0, 2);\n\n  print(arr); \/\/ \u8f93\u51fa [C, D, E, F]\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1astart \u548c end \u7684\u53d6\u503c\u8303\u56f4\u662f 0 \u5230 length\uff0c\u800c\u4e14 start \u5fc5\u987b\u5c0f\u4e8e end\u3002<\/p>\n<\/blockquote>\n
    2.2.5 removeWhere()<\/h4>\n
    \u6570\u7ec4\u7684 removeWhere<\/code> \u65b9\u6cd5\u53ef\u4ee5\u6839\u636e\u7b5b\u9009\u6761\u4ef6\u79fb\u9664\u6307\u5b9a\u7684\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = [1, 2, 3, 4, 5, 6];\n  \/\/ \u6839\u636e\u6761\u4ef6\u79fb\u9664\u5143\u7d20\uff0c\u6240\u6709\u6ee1\u8db3 where \u6761\u4ef6\u7684\u5143\u7d20\u90fd\u4f1a\u88ab\u79fb\u9664\u6389\n  \/\/ \u79fb\u9664\u6240\u6709\u5076\u6570\n  arr.removeWhere((element) => element % 2 == 0);\n\n  print(arr); \/\/ \u8f93\u51fa [1, 3, 5]\n}<\/code><\/pre>\n
    2.2.6 \u4f7f\u7528\u7d22\u5f15\u6e05\u7a7a\u6570\u7ec4<\/h4>\n
    \u53ef\u4ee5\u628a\u6570\u7ec4\u7684 length<\/code> \u8d4b\u503c\u4e3a 0<\/code>\uff0c\u4ece\u800c\u5b9e\u73b0\u6e05\u7a7a\u6570\u7ec4\u7684\u529f\u80fd\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u58f0\u660e\u6570\u7ec4\n  var arr = [1, 2, 3, 4, 5, 6];\n\n  \/\/ \u628a\u6570\u7ec4\u7684 length \u8d4b\u503c\u4e3a 0\n  names.length = 0;\n  \/\/ \u8f93\u51fa true\uff0c\u8bc1\u660e\u662f\u7a7a\u6570\u7ec4\n  print(names.isEmpty);\n}<\/code><\/pre>\n
    2.3 \u63d2\u5165\u5143\u7d20<\/h3>\n
    2.3.1 insert()<\/h4>\n
    \u6570\u7ec4\u7684insert(index, element)<\/code> \u65b9\u6cd5\u53ef\u4ee5\u5411\u6307\u5b9a\u7684\u7d22\u5f15\u4f4d\u7f6e\u63d2\u5165\u5355\u4e2a\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var names = ['\u5b34\u653f', '\u5c0f\u4e54', '\u8521\u6587\u59ec'];\n  \/\/ \u5728\u7d22\u5f15\u4e3a 1 \u7684\u4f4d\u7f6e\u63d2\u5165\u6307\u5b9a\u7684\u5143\u7d20\n  names.insert(1, '\u7504\u59ec');\n  \/\/ \u8f93\u51fa [\u5b34\u653f, \u7504\u59ec, \u5c0f\u4e54, \u8521\u6587\u59ec]\n  print(names);\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u5728\u63d0\u4f9b\u63d2\u5165\u7684\u7d22\u5f15\u65f6\uff0c\u7d22\u5f15\u7684\u53d6\u503c\u8303\u56f4\u662f 0 \u5230 length\uff0c\u5426\u5219\u4f1a\u62a5\u9519\u3002<\/p>\n<\/blockquote>\n
    2.3.2 insertAll()<\/h4>\n
    \u6570\u7ec4\u7684 insertAll(index, elements)<\/code> \u65b9\u6cd5\u53ef\u4ee5\u5411\u6307\u5b9a\u7684\u7d22\u5f15\u4f4d\u7f6e\u63d2\u5165\u591a\u4e2a\u5143\u7d20\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var names = ['\u5b34\u653f', '\u5c0f\u4e54', '\u8521\u6587\u59ec'];\n  \/\/ \u5728\u7d22\u5f15\u4e3a 2 \u7684\u4f4d\u7f6e\u63d2\u5165\u6307\u5b9a\u7684\u5143\u7d20\n  names.insertAll(2, ['\u7504\u59ec', '\u865e\u59ec', '\u9999\u9999']);\n  \/\/ \u8f93\u51fa [\u5b34\u653f, \u5c0f\u4e54, \u7504\u59ec, \u865e\u59ec, \u9999\u9999, \u8521\u6587\u59ec]\n  print(names);\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u5728\u63d0\u4f9b\u63d2\u5165\u7684\u7d22\u5f15\u65f6\uff0c\u7d22\u5f15\u7684\u53d6\u503c\u8303\u56f4\u662f 0 \u5230 length\uff0c\u5426\u5219\u4f1a\u62a5\u9519\u3002<\/p>\n<\/blockquote>\n
    3. List \u5e38\u7528\u65b9\u6cd5<\/h2>\n
    3.1 \u67e5\u627e\u5143\u7d20\u7684\u7d22\u5f15<\/h3>\n
    3.1.1 indexOf<\/h4>\n
    \u6570\u7ec4\u7684 indexOf<\/code> \u65b9\u6cd5\u7528\u6765\u67e5\u627e\u5339\u914d\u5143\u7d20\u7684\u7d22\u5f15\uff0c\u5982\u679c\u5b58\u5728\u591a\u4e2a<\/strong>\u5339\u914d\u7684\u5143\u7d20\uff0c\u53ea\u8fd4\u56de\u7b2c\u4e00\u4e2a<\/strong>\u5339\u914d\u9879\u7684\u7d22\u5f15\u503c\uff0c\u5982\u679c\u6ca1\u6709\u5339\u914d\u7684\u5143\u7d20\u5219\u8fd4\u56de -1<\/code>\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var names = ['\u5b34\u653f', '\u5c0f\u4e54', '\u8521\u6587\u59ec', '\u5c0f\u4e54'];\n  var index = names.indexOf('\u5c0f\u4e54');\n  print(index); \/\/ \u627e\u5230\u4e86\uff0c\u8f93\u51fa 1\n\n  var index2 = names.indexOf('\u5927\u4e54');\n  print(index2); \/\/ \u6ca1\u627e\u5230\uff0c\u8f93\u51fa -1\n}<\/code><\/pre>\n
    3.1.2 lastIndexOf<\/h4>\n
    \u6570\u7ec4\u7684 lastIndexOf<\/code> \u65b9\u6cd5\u7528\u6765\u67e5\u627e\u6700\u540e\u4e00\u4e2a\u5339\u914d\u9879\u7684\u7d22\u5f15\u503c\uff0c\u5982\u679c\u6ca1\u6709\u5339\u914d\u7684\u5143\u7d20\uff0c\u5219\u8fd4\u56de -1<\/code>\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var names = ['\u5b34\u653f', '\u5c0f\u4e54', '\u8521\u6587\u59ec', '\u5c0f\u4e54'];\n\n  var index3 = names.lastIndexOf('\u5c0f\u4e54');\n  print(index3); \/\/ \u627e\u5230\u4e86\uff0c\u8f93\u51fa\u7d22\u5f15 3\n\n  var index4 = names.lastIndexOf('\u5927\u4e54');\n  print(index4); \/\/ \u6ca1\u627e\u5230\uff0c\u8f93\u51fa -1\n}<\/code><\/pre>\n
    3.1.3 \u6839\u636e where \u6761\u4ef6\u67e5\u8be2\u5339\u914d\u9879\u7684\u7d22\u5f15<\/h4>\n
    \u6570\u7ec4\u7684 indexWhere<\/code> \u7528\u6765\u4ece\u5de6\u4fa7\u8fdb\u884c\u6761\u4ef6\u67e5\u627e\uff0clastIndexWhere<\/code> \u7528\u6765\u4ece\u53f3\u4fa7\u8fdb\u884c\u6761\u4ef6\u67e5\u627e\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var names = ['\u5b34\u653f', '\u5c0f\u4e54', '\u8521\u6587\u59ec', '\u5c0f\u4e54'];\n\n  \/\/ \u67e5\u627e\u5143\u7d20 length == 3 \u7684\u5143\u7d20\u7684\u7d22\u5f15\n  var index5 = names.indexWhere((element) => element.length == 3);\n  print(index5); \/\/ \u8f93\u51fa\u7d22\u5f15 2\n\n  \/\/ \u4ece\u53f3\u4fa7\u67e5\u627e\u5143\u7d20\u4e2d\u5305\u542b '\u4e54' \u7684\u5143\u7d20\u7684\u7d22\u5f15\n  var index6 = names.lastIndexWhere((element) => element.contains('\u4e54'));\n  print(index6); \/\/ \u8f93\u51fa\u7d22\u5f15 3\n}<\/code><\/pre>\n
    3.2 \u66ff\u6362\u533a\u95f4\u5143\u7d20<\/h3>\n
    3.2.1 fillRange<\/h4>\n
    \u8c03\u7528\u6570\u7ec4\u7684 fillRange(int start, int end, [E? fillValue]);<\/code> \u65b9\u6cd5\u53ef\u4ee5\u628a\u6307\u5b9a\u533a\u95f4<\/strong>\u7684\u5143\u7d20\u586b\u5145\uff08\u8986\u76d6\uff09<\/strong>\u4e3a\u6307\u5b9a\u7684\u503c\u3002\u586b\u5145\u7684\u8303\u56f4\u662f \u2265start<\/strong> \u7d22\u5f15\uff0c\uff1cend<\/strong> \u7d22\u5f15\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u53ef\u4e3a\u7a7a\u7684 int \u6570\u7ec4\n  List<int?> nums = [1, 2, 3];\n  \/\/ 2. \u6269\u5145\u6570\u7ec4\u957f\u5ea6\u5230 10\n  nums.length = 10;\n  \/\/ 3. \u8f93\u51fa [1, 2, 3, null, null, null, null, null, null, null]\uff0c\u540e 7 \u4e2a\u5143\u7d20\u9ed8\u8ba4\u503c\u4e3a null\n  print(nums);\n\n  \/\/ 4. \u628a\u7d22\u5f15 \u22653 \u5230\u7d22\u5f15\uff1c10 \u7684\u5143\u7d20\u503c\u8986\u76d6\u4e3a\u6570\u5b57 0\n  \/\/ \u6ce8\u610f\uff1a\u7d22\u5f15\u5305\u524d\u4e0d\u5305\u540e\n  nums.fillRange(3, nums.length, 0);\n  \/\/ 5. \u8f93\u51fa [1, 2, 3, 0, 0, 0, 0, 0, 0, 0]\n  print(nums);\n}<\/code><\/pre>\n
    3.2.2 replaceRange<\/h4>\n
    \u8c03\u7528\u6570\u7ec4\u7684 replaceRange(int start, int end, Iterable<E> replacements);<\/code> \u65b9\u6cd5\u53ef\u4ee5\u628a\u6307\u5b9a\u533a\u95f4<\/strong>\u7684\u5143\u7d20\u6574\u4f53\u66ff\u6362<\/strong>\u4e3a\u6307\u5b9a\u7684\u5143\u7d20\u3002\u66ff\u6362\u7684\u8303\u56f4\u662f \u2265start<\/strong> \u7d22\u5f15\uff0c\uff1cend<\/strong> \u7d22\u5f15\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u57fa\u4e8e List.filled() \u6784\u9020\u51fd\u6570\uff0c\u521d\u59cb\u5316 length \u4e3a 10 \u7684\u53ef\u589e\u957f\u6570\u7ec4\uff0c\u5e76\u628a\u6bcf\u9879\u7684\u521d\u503c\u586b\u5145\u4e3a\u6570\u5b57 0\n  List<int> counts = List.filled(10, 0, growable: true);\n  \/\/ 2. \u8f93\u51fa [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]\n  print(counts);\n\n  \/\/ 3. \u628a\u7d22\u5f15 \u22653 \u5230\u7d22\u5f15 \uff1c8 \u7684\u5143\u7d20\uff0c\u6574\u4f53\u66ff\u6362\u4e3a\u5143\u7d20 1 \u548c \u5143\u7d20 2\n  \/\/ \u76f8\u5f53\u4e8e\u628a\u7d22\u5f15 3-7 \u7684\u5143\u7d20\u79fb\u9664\uff0c\u518d\u628a\u6307\u5b9a\u7684\u5143\u7d20\u63d2\u5165\u5230\u7d22\u5f15\u4e3a 3 \u7684\u4f4d\u7f6e\n  counts.replaceRange(3, 8, [1, 2]);\n  \/\/ 4. \u8f93\u51fa [0, 0, 0, 1, 2, 0, 0]\n  print(counts);\n}<\/code><\/pre>\n
    3.2.3 setRange<\/h4>\n
    \u8c03\u7528\u6570\u7ec4\u7684 setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]);<\/code> \u65b9\u6cd5\u53ef\u4ee5\u628a\u6307\u5b9a\u533a\u95f4<\/strong>\u7684\u5143\u7d20\u66ff\u6362\u4e3a\u53e6\u4e00\u4e2a\u6570\u7ec4\u4e2d\u7684\u5143\u7d20<\/strong>\u3002\u66ff\u6362\u7684\u8303\u56f4\u662f \u2265start<\/strong> \u7d22\u5f15\uff0c\uff1cend<\/strong> \u7d22\u5f15\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u52a8\u6001\u5143\u7d20\u7c7b\u578b\u7684\u6570\u7ec4 arr\n  var arr = <dynamic>[1, 2, 3, 4, 5];\n  \/\/ 2. \u5b9a\u4e49\u5b57\u7b26\u6570\u7ec4 characters\n  var characters = ['A', 'B', 'C', 'D', 'E', 'F', 'G'];\n\n  \/\/ 3. \u628a arr \u6570\u7ec4\u7d22\u5f15 \u22651 \u5230\u7d22\u5f15\uff1c4 \u7684\u4e09\u4e2a\u5143\u7d20\uff082\uff0c3\uff0c4\uff09\u66ff\u6362\u4e3a\u65b0\u503c\uff0c\n  \/\/ \u65b0\u503c\u4ece\u6570\u7ec4 characters \u4e2d\u63d0\u53d6\uff0c\u9ed8\u8ba4\u4ece\u7d22\u5f15\u4e3a 0 \u7684\u4f4d\u7f6e\u5f80\u540e\u63d0\u53d6\uff0c\u63d0\u53d6\u7684\u4e2a\u6570\u4e3a end - start\n  \/\/ \u6700\u7ec8\u7ed3\u679c\uff1a\u4ece characters \u6570\u7ec4\u4e2d\u63d0\u53d6\u4e09\u4e2a\u5143\u7d20 A, B, C\uff0c\u5e76\u628a\u8fd9\u4e09\u4e2a\u5143\u7d20\u586b\u5145\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u4ece\u7d22\u5f15\u4e3a 1 \u7684\u4f4d\u7f6e\u5f80\u540e\u586b\u5145\n  arr.setRange(1, arr.length - 1, characters);\n  \/\/ \u8f93\u51fa [1, A, B, C, 5]\n  print(arr);\n}<\/code><\/pre>\n
    \u5728\u8fdb\u884c\u5143\u7d20\u63d0\u53d6\u65f6\uff0c\u53ef\u4ee5\u63d0\u4f9b skipCount<\/code> \u9009\u9879\u6765\u6307\u5b9a\u4ece\u7d22\u5f15\u4e3a\u51e0\u7684\u4f4d\u7f6e\u5f00\u59cb\u63d0\u53d6\uff0c\u4f46\u4e00\u5b9a\u8981\u4fdd\u8bc1\u80fd\u63d0\u53d6\u7684\u5143\u7d20\u6570\u91cf\u6ee1\u8db3 end - start<\/code>\uff0c\u5426\u5219\u4f1a\u62a5\u9519\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u52a8\u6001\u5143\u7d20\u7c7b\u578b\u7684\u6570\u7ec4 arr\n  var arr = <dynamic>[1, 2, 3, 4, 5];\n  \/\/ 2. \u5b9a\u4e49\u5b57\u7b26\u6570\u7ec4 characters\n  var characters = ['A', 'B', 'C', 'D', 'E', 'F', 'G'];\n\n  \/\/ 3. \u628a arr \u6570\u7ec4\u7d22\u5f15 \u22651 \u5230\u7d22\u5f15\uff1c4 \u7684\u4e09\u4e2a\u5143\u7d20\uff082\uff0c3\uff0c4\uff09\u66ff\u6362\u4e3a\u65b0\u503c\uff0c\n  \/\/ \u65b0\u503c\u4ece\u6570\u7ec4 characters \u4e2d\u63d0\u53d6\uff0c\u9ed8\u8ba4\u4ece\u7d22\u5f15\u4e3a 4 \u7684\u4f4d\u7f6e\u5f80\u540e\u63d0\u53d6\uff0c\u63d0\u53d6\u7684\u4e2a\u6570\u4e3a end - start\n  \/\/ \u6700\u7ec8\u7ed3\u679c\uff1a\u4ece characters \u6570\u7ec4\u4e2d\u63d0\u53d6\u4e09\u4e2a\u5143\u7d20 E, F, G\uff0c\u5e76\u628a\u8fd9\u4e09\u4e2a\u5143\u7d20\u586b\u5145\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u4ece\u7d22\u5f15\u4e3a 1 \u7684\u4f4d\u7f6e\u5f80\u540e\u586b\u5145\n  arr.setRange(1, arr.length - 1, characters, 4);\n  \/\/ \u8f93\u51fa [1, E, F, G, 5]\n  print(arr);\n}<\/code><\/pre>\n
    3.3 \u6392\u5e8f\u4e0e\u4e71\u5e8f<\/h3>\n
    \u8c03\u7528\u6570\u7ec4\u7684 shuffle<\/code> \u65b9\u6cd5\u53ef\u4ee5\u968f\u673a\u6253\u4e71\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u987a\u5e8f\uff0c\u8c03\u7528\u6570\u7ec4\u7684 sort<\/code> \u65b9\u6cd5\u53ef\u4ee5\u8fdb\u884c\u6392\u5e8f\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u6570\u7ec4\n  var counts = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];\n  \/\/ 2. \u8c03\u7528 shuffle \u65b9\u6cd5\u968f\u673a\u6253\u4e71\u6570\u7ec4\n  counts.shuffle();\n  \/\/ 3. \u8f93\u51fa\u6253\u4e71\u7684\u7ed3\u679c\u4e3a [4, 8, 9, 5, 2, 10, 6, 7, 3, 1] \u6216\u5176\u5b83\u968f\u673a\u7684\u7ed3\u679c\n  print(counts);\n\n  \/\/ 4. \u76f4\u63a5\u8c03\u7528 sort() \u65b9\u6cd5\u8fdb\u884c\u6392\u5e8f\u65f6\uff0c\u9ed8\u8ba4\u662f\u5347\u5e8f\u6392\u5e8f\n  \/\/ \u5982\u679c\u63d0\u4f9b\u4e86\u6bd4\u8f83\u51fd\u6570\uff0c\u5f53 a - b \u65f6\u8fdb\u884c\u5347\u5e8f\u6392\u5e8f\n  \/\/ \u5982\u679c\u63d0\u4f9b\u4e86\u6bd4\u8f83\u51fd\u6570\uff0c\u5f53 b - a \u65f6\u8fdb\u884c\u964d\u5e8f\u6392\u5e8f\n  \/\/ \u6ce8\u610f\uff1a\u6bd4\u8f83\u51fd\u6570\u7684\u8fd4\u56de\u503c\u5fc5\u987b\u662f\u6570\u5b57\n  counts.sort((a, b) => b - a);\n\n  \/\/ 5. \u8f93\u51fa [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]\n  print(counts);\n}<\/code><\/pre>\n
    \u5982\u679c\u8981\u4e3a\u5b57\u7b26\u4e32\u7684\u6570\u7ec4\u8c03\u7528 sort<\/code> \u8fdb\u884c\u6392\u5e8f\uff0c\u53ef\u4ee5\u5728\u6bd4\u8f83\u51fd\u6570\u4e2d\u4f7f\u7528\u5b57\u7b26\u4e32\u7684 compareTo<\/code> \u65b9\u6cd5\uff0c\u8fd4\u56de\u4e00\u4e2a\u6570\u5b57\u4f9b sort<\/code> \u65b9\u6cd5\u8fdb\u884c\u6392\u5e8f\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u5b57\u7b26\u4e32\u7684\u6570\u7ec4\n  var strs = ['I', 'C', 'U', 'AF', 'D', 'AR', 'A'];\n\n  \/\/ 2. \u76f4\u63a5\u8c03\u7528 sort() \u65b9\u6cd5\u8fdb\u884c\u6392\u5e8f\u65f6\uff0c\u9ed8\u8ba4\u662f\u5347\u5e8f\u6392\u5e8f\n  \/\/ \u5982\u679c\u63d0\u4f9b\u4e86\u6bd4\u8f83\u51fd\u6570\uff0c\u5f53 a.compareTo(b) \u65f6\u8fdb\u884c\u5347\u5e8f\u6392\u5e8f\n  \/\/ \u5982\u679c\u63d0\u4f9b\u4e86\u6bd4\u8f83\u51fd\u6570\uff0c\u5f53 b.compareTo(a) \u65f6\u8fdb\u884c\u964d\u5e8f\u6392\u5e8f\n  strs.sort((a, b) => b.compareTo(a));\n\n  \/\/ 3. \u8f93\u51fa [U, I, D, C, AR, AF, A]\n  print(strs);\n}<\/code><\/pre>\n
    3.4 \u53cd\u8f6c\u6570\u7ec4<\/h3>\n
    \u53cd\u8f6c\u6570\u7ec4\u4f7f\u7528\u7684\u662f reversed<\/code> \u5c5e\u6027\uff0c\u5b83\u4f1a\u8fd4\u56de\u4e00\u4e2a\u53ef\u8fed\u4ee3\u7684\u96c6\u5408\uff0c\u518d\u8c03\u7528 toList<\/code> \u65b9\u6cd5\u53ef\u4ee5\u5f97\u5230\u4e00\u4e2a\u53cd\u8f6c\u540e\u7684\u65b0\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u539f\u6570\u7ec4\n  var arr = [1, 2, 3, 4, 5];\n  \/\/ 2. \u901a\u8fc7\u6570\u7ec4\u7684 reversed \u5c5e\u6027\u5f97\u5230\u4e00\u4e2a\u53ef\u8fed\u4ee3\u7684\u96c6\u5408\n  var newArr = arr.reversed;\n  \/\/ 3. \u8c03\u7528\u53ef\u8fed\u4ee3\u96c6\u5408\u7684 .toList() \u65b9\u6cd5\u53ef\u4ee5\u628a\u5b83\u8f6c\u4e3a\u6570\u7ec4\n  \/\/ \u8f93\u51fa [5, 4, 3, 2, 1]\n  print(newArr.toList());\n}<\/code><\/pre>\n
    3.5 \u62fc\u63a5\u5143\u7d20<\/h3>\n
    join<\/code> \u65b9\u6cd5\u4f1a\u6839\u636e\u6307\u5b9a\u7684\u5b57\u7b26\u4e32\u628a\u6570\u7ec4\u4e2d\u7684\u6bcf\u4e2a\u5143\u7d20\u62fc\u63a5\u5728\u4e00\u8d77\uff0c\u6700\u7ec8\u8fd4\u56de\u62fc\u63a5\u597d\u7684\u5b57\u7b26\u4e32\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ \u5b9a\u4e49\u6570\u7ec4 colors\n  var colors = <String>['red', 'blue', 'cyan', 'orange'];\n\n  \/\/ \u6839\u636e\u6307\u5b9a\u7684\u5b57\u7b26\u4e32\u62fc\u63a5 Set \u4e2d\u7684\u6bcf\u4e2a\u5143\u7d20\n  var result = colors.join(', ');\n  \/\/ \u8f93\u51fa\u5b57\u7b26\u4e32 red, blue, cyan, orange\n  print(result);\n}<\/code><\/pre>\n
    4. \u5176\u5b83\u64cd\u4f5c<\/h2>\n
    4.1 \u6269\u5c55\u64cd\u4f5c\u7b26<\/h3>\n
    Dart \u5728 2.3 \u5f15\u5165\u4e86 \u6269\u5c55\u64cd\u4f5c\u7b26<\/strong>\uff08...<\/code>\uff09\uff0c\u5b83\u53ef\u4ee5\u65b9\u4fbf\u5730\u5408\u5e76\u591a\u4e2a\u96c6\u5408\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u6570\u7ec4 arr1\uff0c\u5305\u542b\u4e09\u4e2a\u6570\u5b57\u5143\u7d20\n  var arr1 = [1, 2, 3];\n\n  \/\/ 2. \u5b9a\u4e49\u6570\u7ec4 arr2\uff0c\u5e76\u628a arr1 \u4e2d\u7684\u6bcf\u4e2a\u5143\u7d20\u5c55\u5f00\uff0c\u63d2\u5165\u5230\u5143\u7d20 0 \u548c\u5143\u7d20 4 \u4e4b\u95f4\n  var arr2 = [0, ...arr1, 4];\n\n  \/\/ 3. \u8f93\u51fa [0, 1, 2, 3, 4]\n  print(arr2);\n}<\/code><\/pre>\n
    4.2 \u7a7a\u611f\u77e5\u6269\u5c55\u64cd\u4f5c\u7b26<\/h3>\n
    Dart \u5728 2.3 \u8fd8\u5f15\u5165\u4e86\u7a7a\u611f\u77e5\u6269\u5c55\u64cd\u4f5c\u7b26<\/strong>\uff08...?<\/code>\uff09\uff0c\u5982\u679c\u6269\u5c55\u64cd\u4f5c\u7b26\u53f3\u8fb9\u53ef\u80fd\u4e3a null<\/code>\uff0c\u53ef\u4ee5\u907f\u514d\u4ea7\u751f\u5f02\u5e38\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u53d8\u91cf arr1 \u7684\u503c\u4e3a null\n  var arr1 = null;\n  \/\/ 2. \u4f7f\u7528\u201c\u7a7a\u611f\u77e5\u6269\u5c55\u64cd\u4f5c\u7b26\u201d\u8fdb\u884c\u96c6\u5408\u7684\u5408\u5e76\n  var arr2 = [0, ...?arr1];\n  \/\/ 3. \u8f93\u51fa [0]\n  print(arr2);\n}<\/code><\/pre>\n
    4.3 \u96c6\u5408\u4e2d\u7684 if<\/h3>\n
    \u5728\u96c6\u5408\u4e2d\u4f7f\u7528\u4e09\u5143\u8fd0\u7b97<\/strong>\u65f6\uff0c\u5fc5\u987b\u4e3a true \u548c false \u63d0\u4f9b\u5bf9\u5e94\u7684\u503c\u3002\u4f46\u5728\u6709\u4e9b\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u53ea\u60f3\u63d0\u4f9b\u6761\u4ef6\u6210\u7acb\u65f6\u5019\u7684\u503c\uff0c\u8fd9\u4e2a\u65f6\u5019\u4e09\u5143\u8fd0\u7b97\u7b26\u5c31\u4e0d\u6ee1\u8db3\u6211\u4eec\u7684\u9700\u6c42\u4e86\uff0c\u4f8b\u5982\uff1a<\/p>\n
    void main(List<String> args) {\n  var age = 16;\n\n  \/\/ \u5982\u679c\u5e74\u9f84 \u226518 \u5c81\uff0c\u5219\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 '\u996e\u9152'\n  \/\/ \u5982\u679c\u5e74\u9f84 <18 \u5c81\uff0c\u5219\u4e0d\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20\n  \/\/ \u5f88\u660e\u663e\uff0c\u4f7f\u7528\u4e09\u5143\u8fd0\u7b97\u65e0\u6cd5\u6ee1\u8db3\u6211\u4eec\u7684\u8981\u6c42\uff0c\u56e0\u4e3a\u5b83\u603b\u662f\u8981\u6c42\u6211\u4eec\u63d0\u4f9b\u4e24\u4e2a\u503c\n  var hobby = ['\u5403\u996d', '\u7761\u89c9', age >= 18 ? '\u996e\u9152' : ''];\n\n  print(hobby.length); \/\/ \u8f93\u51fa 3\n}<\/code><\/pre>\n
    \u4e3a\u4e86\u5b9e\u73b0\u4e0a\u8ff0\u7684\u9700\u6c42\u201c\u5982\u679c\u5e74\u9f84 <18 \u5c81\uff0c\u5219\u4e0d\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20<\/strong>\u201d\uff0c\u6211\u4eec\u80fd\u60f3\u5230\u7684\u529e\u6cd5\u5c31\u662f\u7ed3\u5408 if \u5224\u65ad\uff0c\u6309\u9700\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  var age = 16;\n\n  \/\/ \u5982\u679c\u5e74\u9f84 \u226518 \u5c81\uff0c\u5219\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 '\u996e\u9152'\n  \/\/ \u5982\u679c\u5e74\u9f84 <18 \u5c81\uff0c\u5219\u4e0d\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20\n  var hobby = ['\u5403\u996d', '\u7761\u89c9'];\n\n  \/\/ \u4f7f\u7528 if \u5224\u65ad\uff0c\u53ea\u6709\u6761\u4ef6\u6210\u7acb\uff0c\u624d\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\n  if (age >= 18) {\n    hobby.add('\u996e\u9152');\n  }\n\n  print(hobby.length); \/\/ \u8f93\u51fa 2\n  print(hobby); \/\/ \u8f93\u51fa [\u5403\u996d, \u7761\u89c9]\n}<\/code><\/pre>\n
    \u7ed3\u5408 if \u5224\u65ad\u52a8\u6001\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20\u662f\u4e2a\u597d\u529e\u6cd5\uff0c\u4f46\u662f\u5728\u4ee3\u7801\u5199\u6cd5\u4e0a\u6bd4\u8f83\u7e41\u7410\u3002\u56e0\u6b64\uff0cDart \u63d0\u4f9b\u4e86\u65b0\u8bed\u6cd5\u201c\u5728\u96c6\u5408\u4e2d\u4f7f\u7528 if<\/strong>\u201d\u3002\u4e0a\u9762\u7684\u4ee3\u7801\u53ef\u4ee5\u7b80\u5199\u6210\u4e3a\u5982\u4e0b\u7684\u65b9\u5f0f\uff1a<\/p>\n
    void main(List<String> args) {\n  var age = 16;\n\n  \/\/ \u5982\u679c\u5e74\u9f84 \u226518 \u5c81\uff0c\u5219\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 '\u996e\u9152'\n  \/\/ \u5982\u679c\u5e74\u9f84 <18 \u5c81\uff0c\u5219\u4e0d\u5f80\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20\n  \/\/ \u5728\u96c6\u5408\u4e2d\u4f7f\u7528 if \u5224\u65ad\uff0c\u5982\u679c\u6761\u4ef6\u6210\u7acb\uff0c\u5219\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 '\u996e\u9152'\uff0c\u5426\u5219\u4e0d\u6dfb\u52a0\u4efb\u4f55\u5143\u7d20\n  var hobby = ['\u5403\u996d', '\u7761\u89c9', if (age >= 18) '\u996e\u9152'];\n\n  print(hobby.length); \/\/ \u8f93\u51fa 2\n  print(hobby); \/\/ \u8f93\u51fa [\u5403\u996d, \u7761\u89c9]\n}<\/code><\/pre>\n
    \u53e6\u5916\uff0c\u96c6\u5408\u4e2d\u7684 if <\/code> \u8fd8\u80fd\u4e0e else if<\/code> \u548c else<\/code> \u914d\u5408\u4f7f\u7528\uff0c\u4ece\u800c\u5b9e\u73b0\u66f4\u590d\u6742\u7684\u6761\u4ef6\u5224\u65ad\uff1a<\/p>\n
    void main(List<String> args) {\n  var flag = 'XXX';\n\n  var arr = [\n    'hello',\n    'world',\n    \/\/ \u5982\u679c flag \u7684\u503c\u662f 'ok'\uff0c\u5219\u5411\u6570\u7ec4\u4e2d\u63d2\u5165\u5b57\u7b26\u4e32 '\u6210\u529f'\n    \/\/ \u5982\u679c flag \u7684\u503c\u662f 'no'\uff0c\u5219\u5411\u6570\u7ec4\u4e2d\u63d2\u5165\u5b57\u7b26\u4e32 '\u5931\u8d25'\n    \/\/ \u5426\u5219\uff0c\u5411\u6570\u7ec4\u4e2d\u63d2\u5165\u5b57\u7b26\u4e32 '\u672a\u77e5'\n    if (flag == 'ok') '\u6210\u529f' else if (flag == 'no') '\u5931\u8d25' else '\u672a\u77e5'\n  ];\n\n  \/\/ \u8f93\u51fa [hello, world, \u672a\u77e5]\n  print(arr);\n}<\/code><\/pre>\n
    4.4 \u96c6\u5408\u4e2d\u7684 for<\/h3>\n
    \u96c6\u5408\u4e2d\u7684 for \u5faa\u73af\uff0c\u80fd\u5e2e\u52a9\u6211\u4eec\u66f4\u5feb\u5730\u521d\u59cb\u5316\u96c6\u5408\u4e2d\u5143\u7d20\u7684\u503c\u3002\u4f8b\u5982\uff1a\u521b\u5efa\u4e00\u4e2a\u5305\u542b 1 – 10 \u6570\u5b57\u7684\u6570\u7ec4\uff0c\u7528\u96c6\u5408\u4e2d\u7684 for \u5faa\u73af<\/strong>\u53ef\u4ee5\u66f4\u65b9\u4fbf\u7684\u5b9e\u73b0\u9700\u6c42\u3002\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    void main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u7a7a\u6570\u7ec4\n  var nums = [];\n\n  \/\/ 2. \u5faa\u73af 10 \u6b21\uff0c\u628a\u6bcf\u6b21\u5faa\u73af\u65f6\u7684 i \u6dfb\u52a0\u5230\u6570\u7ec4\u4e2d\n  for (var i = 1; i <= 10; i++) {\n    nums.add(i);\n  }\n\n  \/\/ 3. \u8f93\u51fa [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]\n  print(nums);\n\n  \/\/ ----\n\n  \/\/ 1. \u5728\u96c6\u5408\u5185\u4f7f\u7528 for \u5faa\u73af\uff0c\u628a\u53d8\u91cf i \u7684\u503c\u4f5c\u4e3a\u6bcf\u4e2a\u5143\u7d20\u7684\u503c\u63d2\u5165\u5230\u6570\u7ec4\u4e2d\n  var newNums = [for (var i = 1; i <= 10; i++) i];\n  \/\/ 2. \u8f93\u51fa [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]\n  print(newNums);\n}<\/code><\/pre>\n
    \u540c\u65f6\uff0c\u96c6\u5408\u4e2d\u7684 for \u8fd8\u80fd\u7ed3\u5408\u96c6\u5408\u4e2d\u7684 if \u4e00\u8d77\u4f7f\u7528\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
    \/\/ \u5bfc\u5165 math \u5e93\uff0c\u624d\u53ef\u4ee5\u4f7f\u7528 pow() \u51fd\u6570\nimport 'dart:math';\n\nvoid main(List<String> args) {\n  \/\/ 1. \u5b9a\u4e49\u6570\u7ec4 nums\n  var nums = [11, 22, 33, 44, 55, 66, 77];\n\n  \/\/ 2. \u5faa\u73af\u6570\u7ec4\u4e2d\u7684\u6bcf\u4e00\u9879\uff0c\u5982\u679c\u662f\u5076\u6570\uff0c\u5219\u6c42\u5e73\u65b9\uff1b\u5982\u679c\u662f\u5947\u6570\uff0c\u5219\u6c42\u7acb\u65b9\n  \/\/ \u6700\u7ec8\u628a\u65b0\u503c\u5b58\u50a8\u6570\u7ec4 newNums \u4e2d\n  var newNums = [\n    for (var i = 0; i < nums.length; i++)\n      if (nums[i] % 2 == 0) pow(nums[i], 2) else pow(nums[i], 3)\n  ];\n\n  \/\/ 3. \u8f93\u51fa [1331, 484, 35937, 1936, 166375, 4356, 456533]\n  print(newNums);\n}<\/code><\/pre>\n
    \n
    \u6ce8\u610f\uff1a\u4e0a\u9762\u7684\u793a\u4f8b\u53ea\u662f\u4ece\u4ee3\u7801\u5c42\u9762\u505a\u4e86\u6f14\u793a\uff0c\u5b9e\u9645\u5f00\u53d1\u4e2d\u8fd8\u8981\u6839\u636e\u4e1a\u52a1\u573a\u666f\u6765\u51b3\u5b9a\u662f\u5426\u4f7f\u7528\u5b83\u4eec\u3002<\/p>\n<\/blockquote>\n
    \u5173\u4e8e List \u96c6\u5408\u4e2d\u7684\u66f4\u591a\u7528\u6cd5\uff0c\u8bf7\u53c2\u8003 List \u7684\u5b98\u65b9\u6587\u6863<\/a>\u3002<\/p>\n
    \n
    \u7248\u6743\u5f52\u4f5c\u8005 \u00a9\u5218\u9f99\u5bbe<\/strong> \u6240\u6709\uff0c\u672c\u6587\u7ae0\u672a\u7ecf\u4f5c\u8005\u5141\u8bb8\uff0c\u7981\u6b62\u79c1\u81ea\u8f6c\u8f7d\uff01<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"
    \u7248\u6743\u5f52\u4f5c\u8005 \u00a9\u5218\u9f99\u5bbe \u6240\u6709\uff0c\u672c\u6587\u7ae0\u672a\u7ecf\u4f5c\u8005\u5141\u8bb8\uff0c\u7981\u6b62\u79c1\u81ea\u8f6c\u8f7d\uff01 \u5728 Dart \u7684\u5185\u7f6e\u7c7b\u578b\u4e2d\uff0c\u96c6\u5408\u76f8\u5173\u7684\u7c7b\u578b\u5171\u67093\u4e2a\uff0c\u5206\u522b\u662f\uff1a List Set Map \u5176\u4e2d List \u96c6\u5408\u5c31\u662f\u5176\u5b83\u8bed\u8a00\u4e2d\u6240\u8c13\u7684\u6570\u7ec4\uff08Array\uff09\uff0c\u5728 Dart \u4e2d\u6570\u7ec4\u7528 List \u5bf9\u8c61\u8868\u793a\uff0c\u672c\u8282\u4e3b\u8981\u8ba8\u8bba\u5b83\u7684\u57fa\u672c\u4f7f\u7528\u3002 1. \u58f0\u660e List \u6570\u7ec4 1.1 \u57fa\u4e8e\u5b57\u9762\u91cf\u521b\u5efa List 1.1.1 \u5b8c\u6574\u5f62\u5f0f \u57fa\u4e8e\u5b57\u9762\u91cf <\u7c7b\u578b>[] \u662f\u521b\u5efa List \u6570\u7ec4\u6700\u7b80\u5355\u7684\u65b9\u5f0f\u3002\u4f8b\u5982\uff0c\u4e0b\u9762\u7684\u4ee3\u7801\u521b\u5efa\u4e86\u4e00\u4e2a\u7a7a\u6570\u7ec4 arr\uff0c\u7528\u6765\u5b58\u50a8 int \u7c7b\u578b\u7684\u5143\u7d20\uff1a void main(List<String> args) { \/\/ 1. \u53f3\u4fa7\u7684 <int> \u7528\u6765\u6307\u5b9a [] \u4e2d\u5b58\u50a8\u7684\u5143\u7d20\u7684\u6570\u636e\u7c7b\u578b\u5fc5\u987b\u662f int \u6570\u5b57 \/\/ 2. \u5de6\u4fa7\u7684 List<int> \u8868\u793a arr \u53d8\u91cf\u7684\u7c7b\u578b\u662f List \u6570\u7ec4\uff0c\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u7c7b\u578b\u662f int List<int> arr = <int>[]; \/\/ 3. length \u5c5e\u6027\u7528\u6765\u67e5\u770b\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u4e2a\u6570 print(arr.length); \/\/ \u8f93\u51fa 0 \/\/ 4. isEmpty \u5c5e\u6027\u7528\u6765\u5224\u65ad\u6570\u7ec4\u662f\u5426\u4e3a\u7a7a print(arr.isEmpty); \/\/ \u8f93\u51fa true } 1.1.2 \u7c7b\u578b\u7b80\u5199 List<int> arr = <int>[]; \u662f\u57fa\u4e8e\u5b57\u9762\u91cf\u521b\u5efa\u6570\u7ec4\u7684\u5b8c\u6574\u5f62\u5f0f\u3002\u5176\u4e2d\uff0c\u53f3\u4fa7\u7684 <int> \u548c\u5de6\u4fa7\u7684 List<int> \u90fd\u6307\u5b9a\u4e86\u6570\u7ec4\u5143\u7d20\u7684\u7c7b\u578b\uff0c\u5728\u5199\u6cd5\u4e0a\u6709\u4e9b\u5197\u4f59\u3002\u6211\u4eec\u53ef\u4ee5\u6309\u9700\u7701\u7565\u5de6\u4fa7\u6216\u53f3\u4fa7\u7684\u7c7b\u578b\uff0c\u4f9d\u7136\u80fd\u4fdd\u8bc1 arr \u662f int \u7c7b\u578b\u7684\u6570\u7ec4\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a void main(List<String> args) { \/\/ List<int> arr = <int>[]; \/\/ \u5b8c\u6574\u5199\u6cd5\uff0c\u5de6\u4fa7\u548c\u53f3\u4fa7\u90fd\u5305\u542b\u7c7b\u578b\u58f0\u660e \/\/ var arr = <int>[]; \/\/ \u628a\u5de6\u8fb9\u7684\u7c7b\u578b\u7701\u7565\uff0c\u53f3\u4fa7\u7684 <int> \u8868\u793a arr \u662f int \u7c7b\u578b\u7684\u6570\u7ec4 \/\/ List<int> arr = []; \/\/ \u628a\u53f3\u8fb9\u7684\u7c7b\u578b\u7701\u7565\uff0c\u5de6\u4fa7\u7684 List<int> \u8868\u793a arr \u662f int \u7c7b\u578b\u7684\u6570\u7ec4 } \u4e0a\u9762\u7684\u4ee3\u7801\u7b80\u5316\u4e86\u5b9a\u4e49\u6570\u7ec4\u65f6\u7684\u7c7b\u578b\u58f0\u660e\uff0c\u4ee3\u7801\u66f4\u4e3a\u7b80\u6d01\uff0c\u540c\u65f6\u8fd8\u80fd\u4fdd\u8bc1\u6570\u7ec4\u4e2d\u5143\u7d20\u7684\u7c7b\u578b\uff0c\u4f8b\u5982\u5411 int \u6570\u7ec4\u4e2d\u6dfb\u52a0\u5176\u5b83\u7c7b\u578b\u7684\u5143\u7d20\u65f6\uff0c\u4ee3\u7801\u4f1a\u62a5\u9519\uff1a void main(List<String> args) { \/\/ 1. \u58f0\u660e int \u7c7b\u578b\u7684\u6570\u7ec4 arr var arr = <int>[]; \/\/ 2. \u8c03\u7528\u6570\u7ec4\u7684 add() \u65b9\u6cd5\uff0c\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u5143\u7d20 \/\/ int \u7c7b\u578b\u7684\u6570\u5b57 1 \u53ef\u4ee5\u6b63\u5e38\u7684\u6dfb\u52a0\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u56e0\u4e3a\u5143\u7d20\u7684\u7c7b\u578b\u548c\u6570\u7ec4\u7684\u7c7b\u578b\u5339\u914d arr.add(1); \/\/ 3. \u5b57\u7b26\u4e32 'abc' \u65e0\u6cd5\u88ab\u6dfb\u52a0\u5230\u6570\u7ec4 arr \u4e2d\uff0c\u56e0\u4e3a\u7c7b\u578b\u4e0d\u5339\u914d\uff0c\u6240\u4ee5\u4e0b\u9762\u8fd9\u884c\u4ee3\u7801\u7f16\u8bd1\u4f1a\u62a5\u9519 arr.add('abc'); } 1.1.3 dynamic \u6570\u7ec4 \u6ce8\u610f\uff0c\u5982\u679c\u540c\u65f6\u7701\u7565\u4e86\u5de6\u4fa7\u548c\u53f3\u4fa7\u7684\u7c7b\u578b\uff0c\u5219\u8868\u793a\u58f0\u660e\u4e86\u4e00\u4e2a dynamic \u7c7b\u578b\u7684\u6570\u7ec4\u3002\u6b64\u65f6\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u6dfb\u52a0\u4e0d\u540c\u7c7b\u578b\u7684\u5143\u7d20\uff0c\u76f8\u5f53\u4e8e\u89e3\u9664\u4e86\u6570\u7ec4\u4e2d\u5143\u7d20\u7c7b\u578b\u5fc5\u987b\u4e00\u81f4\u7684\u9650\u5236\uff0c\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a void main(List<String> args) { \/\/ 1. \u5b8c\u6574\u5199\u6cd5\uff0c\u5de6\u4fa7\u548c\u53f3\u4fa7\u90fd\u5305\u542b\u7c7b\u578b\u58f0\u660e\uff0c\u628a arr \u9650\u5b9a\u4e3a\u4e86 int \u7c7b\u578b\u7684\u6570\u7ec4 \/\/ List<int> arr = <int>[]; \/\/ 2. \u540c\u65f6\u7701\u7565\u4e24\u8fb9\u7684\u7c7b\u578b\uff0c\u8868\u793a\u58f0\u660e\u4e86 dynamic \u52a8\u6001\u7c7b\u578b\u7684\u6570\u7ec4\uff0c \/\/ \u7b49\u540c\u4e8e\u5b8c\u6574\u5199\u6cd5\u7684\u58f0\u660e\u65b9\u5f0f\uff1a List<dynamic> arr = <dynamic>[]; \/\/ \u6b64\u65f6\u53ef\u4ee5\u5411\u6570\u7ec4\u4e2d\u5b58\u50a8\u4efb\u610f\u7c7b\u578b\u7684\u5143\u7d20 var arr = []; \/\/ 3.1 \u6dfb\u52a0\u6570\u5b57 1 arr.add(1); \/\/ 3.2 \u6dfb\u52a0\u5b57\u7b26\u4e32 'abc' arr.add('abc'); \/\/ 3.3 \u6dfb\u52a0\u5e03\u5c14\u503c true arr.add(true); \/\/ 4. \u8f93\u51fa [1, abc, true] print(arr); } 1.1.4 \u5e38\u91cf\u6570\u7ec4 \u5728 Dart \u4e2d\uff0c\u53ef\u4ee5\u57fa\u4e8e const \u58f0\u660e\u7f16\u8bd1\u65f6\u7684\u5e38\u91cf\u6570\u7ec4\u3002\u4f7f\u7528 const \u58f0\u660e\u7684\u6570\u7ec4\u662f unmodifiable \u7684 List\uff0c\u5373 \u201c\u4e0d\u53ef\u4fee\u6539\u201d\u7684\u6570\u7ec4\u3002\u65e0\u6cd5\u5220\u9664\u5143\u7d20\u3001\u4fee\u6539\u5143\u7d20\u3001\u6269\u5145\u6570\u7ec4\u957f\u5ea6\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a void main(List<String> args) { \/\/ 1…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[9],"class_list":["post-196","post","type-post","status-publish","format-standard","hentry","category-dart","tag-dart"],"_links":{"self":[{"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/posts\/196","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/comments?post=196"}],"version-history":[{"count":3,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/posts\/196\/revisions"}],"predecessor-version":[{"id":577,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/posts\/196\/revisions\/577"}],"wp:attachment":[{"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/media?parent=196"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/categories?post=196"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.escook.cn\/index.php\/wp-json\/wp\/v2\/tags?post=196"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}