{"id":278976,"date":"2022-09-16T04:00:00","date_gmt":"2022-09-16T03:00:00","guid":{"rendered":"https:\/\/blog.jetbrains.com\/dotnet\/2022\/08\/30\/refactor-code-to-use-new-c-language-features\/"},"modified":"2022-09-15T04:47:40","modified_gmt":"2022-09-15T03:47:40","slug":"refactor-code-to-use-new-c-language-features","status":"publish","type":"dotnet","link":"https:\/\/blog.jetbrains.com\/zh-hans\/dotnet\/2022\/09\/16\/refactor-code-to-use-new-c-language-features\/","title":{"rendered":"\u91cd\u6784\u4ee3\u7801\u4ee5\u4f7f\u7528\u65b0\u7684 C# \u8bed\u8a00\u529f\u80fd"},"content":{"rendered":"\n<p>\u5728\u4f7f\u7528\u4efb\u4f55\u8bed\u8a00\u65f6\uff0c\u5411\u73b0\u4ee3\u8bed\u8a00\u529f\u80fd\u8fdb\u884c\u73b0\u4ee3\u5316\u6539\u9020\u6216\u8fc1\u79fb\u6709\u52a9\u4e8e\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u3001\u6548\u7387\u548c\u5b89\u5168\u6027\u3002\u5728\u8fd9\u7bc7\u535a\u6587\u4e2d\uff0c\u6211\u4eec\u5c06\u7814\u7a76\u5bf9\u4ee3\u7801\u8fdb\u884c\u73b0\u4ee3\u5316\u6539\u9020\u7684\u65b9\u5f0f\uff0c\u4ece\u800c\u4f18\u5316\u4ee3\u7801\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5229\u7528\u73b0\u4ee3\u8bed\u8a00\u529f\u80fd<\/h2>\n\n\n\n<p>\u4e3a\u4f55\u53ea\u4e3a\u4f7f\u4ee3\u7801\u73b0\u4ee3\u5316\u5c31\u8981\u91cd\u6784\u4ee3\u7801\uff1f\u5018\u82e5\u5b8c\u597d\uff0c\u4f55\u5fc5\u4fee\u6b63\uff1f\u6709\u65f6\uff0c\u4eba\u4eec\u4f1a\u6709\u5145\u5206\u7684\u7406\u7531\u53bb\u5347\u7ea7\u6216\u8fc1\u79fb\u5230\u65b0\u7248\u672c\u7684\u5e73\u53f0\u6216\u8bed\u8a00\u3002\u4f8b\u5982\uff0c\u8bed\u8a00\u9010\u6e10\u6f14\u53d8\u5e76\u6dfb\u52a0\u4e86\u529f\u80fd\uff0c\u4ee5\u4fbf\u5229\u7528\u64cd\u4f5c\u7cfb\u7edf\u529f\u80fd\u3001\u8bbe\u5907\u548c\u6d4f\u89c8\u5668\u529f\u80fd\u3001\u4e91\u6216\u5176\u4ed6\u6280\u672f\u3002\u6b64\u5916\uff0c<strong>\u8bed\u8a00\u66f4\u65b0\u8fd8\u5305\u62ec\u5f15\u5165\u9519\u8bef\u4fee\u6b63\u3001\u66f4\u7b80\u6d01\u7684\u8bed\u6cd5\u548c\u8bed\u6cd5\u7cd6\uff0c\u4ee5\u53ca\u66f4\u9ad8\u6548\u7684\u5bf9\u8c61\u548c\u6570\u636e\u5904\u7406\u65b9\u5f0f<\/strong>\u3002<\/p>\n\n\n\n<p>\u5bf9\u4ee3\u7801\u8fdb\u884c\u73b0\u4ee3\u5316\u6539\u9020\u7684\u91cd\u6784\u53ef\u4ee5\u901a\u8fc7<a href=\"https:\/\/blog.jetbrains.com\/dotnet\/2021\/02\/08\/make-code-more-readable-by-refactoring-with-resharper\/\">\u63d0\u9ad8\u53ef\u8bfb\u6027<\/a>\u548c\u53ef\u7ef4\u62a4\u6027\u6765\u663e\u8457\u63d0\u9ad8\u4ee3\u7801\u8d28\u91cf\u3002\u8fd9\u662f\u56e0\u4e3a\u968f\u7740\u8bed\u8a00\u7684\u9010\u6e10\u6f14\u53d8\uff0c\u65b0\u6dfb\u52a0\u7684\u8bed\u6cd5\u5f80\u5f80\u4f1a\u6709\u52a9\u4e8e\u51cf\u5c11\u60a8\u5fc5\u987b\u7f16\u5199\u7684\u4ee3\u7801\u884c\u6570\u5e76\u964d\u4f4e\u4ee3\u7801\u7684\u590d\u6742\u6027\u3002<\/p>\n\n\n\n<p>ReSharper \u548c Rider \u7b49\u5de5\u5177\u53ef\u4ee5\u5e2e\u52a9\u60a8\u5b9e\u73b0\u4ee3\u7801\u5e93\u7684\u73b0\u4ee3\u5316\u3002\u5b83\u4eec\u4f1a\u968f\u65f6\u66f4\u65b0\u4ee5\u652f\u6301 .NET \u8bed\u8a00\u7684\u65b0\u529f\u80fd\uff0c\u5e76\u4e14\u53ef\u4ee5\u5728\u6709\u673a\u4f1a\u5145\u5206\u5229\u7528\u8fd9\u4e9b\u529f\u80fd\u65f6\u63d0\u4f9b\u5efa\u8bae\u3002\u9644\u5e26\u7684\u597d\u5904\u662f\uff0c\u8fd9\u4e9b\u5efa\u8bae\u6709\u52a9\u4e8e\u4f7f\u60a8\u7684\u56e2\u961f\u4e0d\u65ad\u66f4\u65b0\u81ea\u8eab\u7684 C# \u6280\u80fd\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u9876\u7ea7\u8bed\u53e5<\/h2>\n\n\n\n<p><a href=\"https:\/\/blog.jetbrains.com\/dotnet\/2020\/10\/08\/top-level-statements-in-resharper-and-rider\/\">\u9876\u7ea7\u8bed\u53e5<\/a>\u5728 C# 9 \u4e2d\u5f15\u5165\uff0c\u4f7f\u60a8\u65e0\u9700\u606a\u5b88\u663e\u5f0f\u5b9a\u4e49\u547d\u540d\u7a7a\u95f4\u6216\u7c7b\u7684\u65e7\u89c4\u5373\u53ef\u7acb\u5373\u5f00\u59cb\u7f16\u5199\u4ee3\u7801\u3002\u5728\u5f15\u5165\u9876\u7ea7\u8bed\u53e5\u4e4b\u524d\uff0c\u5373\u4f7f\u662f\u6253\u5370\u5355\u4e2a\u201cHello World\u201d\u98ce\u683c\u6d88\u606f\u7684\u6700\u57fa\u7840\u5e94\u7528\uff0c\u4e5f\u9700\u8981\u5305\u542b\u4e09\u5c42\u5d4c\u5957\u4e2d\u62ec\u53f7\u624d\u80fd\u652f\u6301\u4e00\u884c\u5b9e\u9645\u8fd0\u884c\u4ee3\u7801\u3002\u8fd9\u6837\u5c31\u4f1a\u7275\u626f\u5230\u5927\u91cf\u4e0d\u5fc5\u8981\u7684\u6837\u677f\u4ee3\u7801\u3002\u8fd9\u771f\u7684\u6709\u5fc5\u8981\u5417\uff1f<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">using System;\n\nnamespace HelloWorld\n{\n    class Program\n    {\n        static void Main(string[] args)\n        {\n            Console.WriteLine(\"Hello, modernized world!\");\n        }\n    }\n}\n<\/pre>\n\n\n\n<p>\u4e0d\uff01\u6211\u4eec\u5b8c\u5168\u6ca1\u6709\u5fc5\u8981\u4f7f\u7528\u4efb\u4f55\u989d\u5916\u7684\u4ee3\u7801\u3002\u501f\u52a9\u9876\u7ea7\u8bed\u53e5\uff0c\u6211\u4eec\u53ef\u4ee5\u5220\u9664 Hello World \u5e94\u7528\u4e2d\u6bcf\u4e00\u884c\u591a\u4f59\u7684\u4ee3\u7801\uff0c\u800c\u4ec5\u4ec5\u4fdd\u7559\u5b9e\u9645\u6267\u884c\u67d0\u4e9b\u529f\u80fd\u7684\u90a3\u4e00\u884c\u4ee3\u7801\u3002<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">System.Console.WriteLine(\"Hello, modernized world!\");<\/pre>\n\n\n\n<p>\u5bf9\u4e8e\u60f3\u8981\u4f7f\u7528\u77ed\u540d\u79f0\u7684\u5f00\u53d1\u8005\uff0c\u4ee3\u7801\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">using static System.Console;\nWriteLine(\"Hello, modernized world!\");<\/pre>\n\n\n\n<p>\u4f7f\u7528\u65b0\u5efa\u9879\u76ee\u6a21\u677f\uff08<strong>File | New Project<\/strong>\uff08\u6587\u4ef6 | \u65b0\u5efa\u9879\u76ee\uff09\uff09\u65f6\uff0c\u4f1a\u9ed8\u8ba4\u4f7f\u7528\u9876\u7ea7\u8bed\u53e5\u3002\u8981\u8fc1\u79fb\u4ee3\u7801\u4ee5\u4f7f\u7528\u9876\u7ea7\u8bed\u53e5\uff0c\u8bf7\u5220\u9664\u547d\u540d\u7a7a\u95f4\u548c\u7c7b\u58f0\u660e\u4ee5\u53ca main \u51fd\u6570\u3002\u53ea\u4fdd\u7559 main \u51fd\u6570\u7684\u4e3b\u4f53\u3002\u5220\u9664\u4ee3\u7801\u5f88\u6709\u8da3\uff0c\u4f46\u5f88\u5bb9\u6613\u6f0f\u6389\u4e2d\u62ec\u53f7\uff0c\u56e0\u6b64\u8bf7\u5728\u5305\u542b&nbsp;<code>Main<\/code>&nbsp;\u7684\u7c7b\u4e0a\u4f7f\u7528&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u5e76\u9009\u62e9&nbsp;<strong>Convert to top-level code<\/strong>\uff08\u8f6c\u6362\u4e3a\u9876\u7ea7\u4ee3\u7801\uff09\u3002\u5c31\u662f\u8fd9\u6837\uff01\u4e00\u5207\u66f4\u65b0\u5b8c\u6bd5\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img decoding=\"async\" loading=\"lazy\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/image-22.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-top-level-code.png\" alt=\"Use top level statements in C#\" class=\"wp-image-265703\" width=\"499\" height=\"352\"><\/figure>\n\n\n\n<p>\u9876\u7ea7\u8bed\u53e5\u6700\u521d\u4e8e C# 9 \u4e2d\u5f15\u5165\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4<\/h2>\n\n\n\n<p>\u547d\u540d\u7a7a\u95f4\u662f\u547d\u540d\u3001\u7ec4\u7ec7\u548c\u8bbf\u95ee\u5bf9\u8c61\u7684\u7edd\u4f73\u65b9\u6cd5\uff0c\u4f46\u60a8\u5e76\u4e0d\u4e00\u5b9a\u8981\u59cb\u7ec8\u4f7f\u7528\u5b83\u4eec\u3002.NET \u4e2d\u5e38\u89c1\u7684\u6587\u4ef6\u7ec4\u7ec7\u6a21\u5f0f\u662f\u6bcf\u4e2a\u6587\u4ef6\u4f7f\u7528\u4e00\u4e2a\u7c7b\uff0c\u4f46\u771f\u7684\u6709\u5fc5\u8981\u5c06\u5355\u4e2a\u7c7b\u5305\u542b\u5728\u547d\u540d\u7a7a\u95f4\u4e2d\u5417\uff1f\u8fd9\u5c31\u662f\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4\u7684\u7528\u6b66\u4e4b\u5730\u3002\u5c31\u50cf\u4f7f\u7528\u9876\u7ea7\u8bed\u53e5\u4e00\u6837\uff0c\u60a8\u9700\u8981\u62c5\u5fc3\u7684\u7f29\u8fdb\u95ee\u9898\u51cf\u5c11\u4e86\u4e00\u7ea7\u3002\u5bf9\u4e8e\u8bed\u6cd5\uff1a\u5728\u6587\u4ef6\u9876\u90e8\u58f0\u660e\u4e00\u4e2a\u547d\u540d\u7a7a\u95f4\u5e76\u7acb\u5373\u4ee5\u5206\u53f7\u7ed3\u675f\uff0c\u5927\u529f\u544a\u6210\u3002\u65e0\u9700\u4e2d\u62ec\u53f7\uff01\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">namespace MealPlanner.Menu;<\/pre>\n\n\n\n<p>\u5c31\u662f\u8fd9\u6837\u3002\u8fd9\u4e00\u884c\u4ee3\u7801\u4fbf\u53ef\u544a\u77e5\u7f16\u8bd1\u5668\u5c06\u6587\u4ef6\u4e2d\u7684\u6240\u6709\u5185\u5bb9\u5168\u90e8\u5305\u542b\u5728&nbsp;<code>MealPlanner.Menu<\/code>&nbsp;\u547d\u540d\u7a7a\u95f4\u4e2d\u3002\u8981\u4f7f\u7528 Rider \u8f6c\u6362\u4e3a\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4\uff0c\u53ea\u9700\u5728\u547d\u540d\u7a7a\u95f4\u58f0\u660e\u4e0a\u6309&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u5e76\u9009\u62e9&nbsp;<strong>To file-scoped namespaces<\/strong>\uff08\u8f6c\u6362\u4e3a\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4\uff09\u5373\u53ef\u3002\u9009\u62e9\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4\u5e94\u5f53\u4ec5\u5e94\u7528\u4e8e\u6b64\u6587\u4ef6\u8fd8\u662f\u5347\u7ea7\u6574\u4e2a\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n\n\n\n<p>\u6587\u4ef6\u8303\u56f4\u547d\u540d\u7a7a\u95f4\u5728 C# 10 \u4e2d\u9996\u6b21\u4eae\u76f8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Init-only setter \u548c\u7d22\u5f15\u5668<\/h2>\n\n\n\n<p>\u6709\u65f6\uff0c\u60a8\u9700\u8981\u5b9e\u4f8b\u5316\u4e00\u4e2a\u5bf9\u8c61\uff0c\u4f46\u5176\u6570\u636e\u5e94\u5f53\u4e0d\u53ef\u53d8\uff08\u4e0d\u53ef\u66f4\u6539\uff09\u3002\u4e5f\u8bb8\u60a8\u5177\u6709&nbsp;<a href=\"https:\/\/en.wikipedia.org\/wiki\/Data_transfer_object\" target=\"_blank\" rel=\"noopener\">DTO<\/a>&nbsp;\u6216\u8868\u793a\u6570\u636e\u5e93\u4e2d\u8868\u7684\u5bf9\u8c61\u3002\u6b64\u7c7b\u5bf9\u8c61\u53ef\u80fd\u5305\u542b\u8868\u548c\u5b57\u6bb5\u7684\u540d\u79f0\uff0c\u56e0\u6b64\u8be5\u5bf9\u8c61\u5e94\u5f53\u4e0d\u53ef\u53d8\u3002\u65e0\u6cd5\u4ece\u6784\u9020\u51fd\u6570\u5916\u90e8\u521d\u59cb\u5316\u8fd9\u79cd\u53ea\u8bfb\u6570\u636e\u3002\u56e0\u6b64\uff0c\u5728\u65e9\u671f\u7248\u672c\u7684 C# \u4e2d\uff0c\u60a8\u9700\u8981\u5728\u6784\u9020\u51fd\u6570\u4e2d\u58f0\u660e\u548c\u521d\u59cb\u5316\u5bf9\u8c61\uff0c\u5e76\u901a\u8fc7\u4ec5\u521b\u5efa\u4e0d\u5e26 setter \u7684 getter \u6765\u5c06\u5c5e\u6027\u8bbe\u4e3a\u53ea\u8bfb\uff0c\u7c7b\u4f3c\u4e8e\u4ee5\u4e0b\u4ee3\u7801\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">class Column\n{\n    public Column(string ColumnName, \nstring DataType, string IsPrimaryKey)\n    {\n        ColumnName = \"Column1\";\n        DataType = \"varchar(20)\";\n        IsPrimaryKey = false;\n    }\n    public string ColumnName { get; }\n    public string DataType { get;  }\n    public bool IsPrimaryKey { get;  }\n}\n\nvar c = new Column();\n<\/pre>\n\n\n\n<p>\u7136\u800c\uff0c\u7ecf\u5178\u7684\u5b9e\u4f8b\u5316\u548c\u521d\u59cb\u5316\u65b9\u5f0f\u610f\u5473\u7740\u6570\u636e\u5fc5\u987b\u4ece\u7c7b\u5185\u90e8\u8fdb\u884c\u8bbe\u7f6e\uff0c\u6784\u9020\u51fd\u6570\u5c31\u662f\u552f\u4e00\u4f4d\u7f6e\u3002\u901a\u5e38\uff0c\u9700\u8981\u4ece\u7c7b\u7684\u5916\u90e8\u8bbe\u7f6e\u6570\u636e\uff0c\u5c24\u5176\u662f\u5728\u4f7f\u7528\u8868\u793a\u6570\u636e\u5e93\u7ed3\u6784\u7684\u5bf9\u8c61\uff08\u5982\u672c\u4f8b\uff09\u65f6\u3002\u501f\u52a9 init-only \u5c5e\u6027\uff0c\u6211\u4eec\u53ef\u4ee5\u521b\u5efa\u5177\u6709\u5728\u8c03\u7528\u4ee3\u7801\u65f6\u4f1a\u521d\u59cb\u5316\u7684\u53ea\u8bfb\u5c5e\u6027\u7684\u5bf9\u8c61\u3002\u76f8\u6bd4\u4ee5\u5f80\uff0c\u8fd9\u6837\u66f4\u52a0\u7075\u6d3b\u3002<\/p>\n\n\n\n<p>\u8981\u5bf9\u4ee3\u7801\u8fdb\u884c\u73b0\u4ee3\u5316\u6539\u9020\u4ee5\u4f7f\u7528 init-only setter\uff0c\u8bf7\u4f7f\u7528 getter \u521b\u5efa\u4e00\u4e2a\u5c5e\u6027\u5e76\u5bf9 setter \u4f7f\u7528&nbsp;<code>init<\/code>&nbsp;\u5173\u952e\u5b57\u800c\u975e&nbsp;<code>set<\/code>\uff08\u6216\u5b8c\u5168\u5220\u9664&nbsp;<code>set<\/code>&nbsp;\u8bed\u53e5\uff09\u3002\u60a8\u5f88\u53ef\u80fd\u4f1a\u9700\u8981\u6279\u91cf\u5347\u7ea7\u8fd9\u4e9b\u5185\u5bb9 \u2013 \u90a3\u4e48\u8bf7\u6309&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u5e76\u9009\u62e9&nbsp;<strong>To init accessor<\/strong>\uff08\u8f6c\u6362\u4e3a\u521d\u59cb\u5316\u8bbf\u95ee\u5668\uff09\uff0c\u7136\u540e\u9009\u62e9\u8303\u56f4\uff1a\u6587\u4ef6\u3001\u9879\u76ee\u6216\u89e3\u51b3\u65b9\u6848\u3002\u7136\u540e\uff0c\u4f7f\u7528\u8005<em>\u5fc5\u987b<\/em>\u5728\u521b\u5efa\u7c7b\u5b9e\u4f8b\u6216\u51fa\u73b0\u7f16\u8bd1\u5668\u9519\u8bef\u65f6\u521d\u59cb\u5316\u8be5\u7c7b\u3002\u8bf7\u6ce8\u610f\u4ee3\u7801\u884c\u6570\u7684\u51cf\u5c11\u3002\u5728\u4e0b\u9762\u7684\u52a8\u753b\u4e2d\uff0c\u7070\u663e\u7684\u4ee3\u7801\u8868\u793a\u53ef\u4ee5\u5b89\u5168\u5730\u5220\u9664\u3002\u4e0d\u518d\u9700\u8981\u6216\u4f7f\u7528\u8fd9\u4e9b\u5185\u5bb9\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-init-only-properties-1.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-init-only-properties.png\" alt=\"Rider Converts a setter to an init only property\" class=\"wp-image-265980\" width=\"500\"><\/figure>\n\n\n\n<pre class=\"wp-block-preformatted\">class Column\n{\n    public string ColumnName { get; init; }\n    public string DataType { get; init; }\n    public bool IsPrimaryKey { get; init; }\n}\n\nvar c = new Column\n{\n    ColumnName = \"First_Name\"\n};\n<\/pre>\n\n\n\n<p>Init-only \u5c5e\u6027\u4e8e C# 9 \u4e2d\u5f15\u5165\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Record \u548c Record Struct<\/h2>\n\n\n\n<p>Record \u662f\u4e00\u79cd\u53ef\u4f7f\u6574\u4e2a\u5bf9\u8c61\u4e0d\u53ef\u53d8\u7684\u65b9\u5f0f\uff0c\u4e0d\u540c\u4e8e\u5728 init-only \u5c5e\u6027\u4e2d\u627e\u5230\u7684\u5355\u4e2a\u5c5e\u6027\u3002Record \u4e0d\u540c\u4e8e\u7c7b\uff0c\u56e0\u4e3a record \u7c7b\u578b\u4f1a\u4f7f\u7528<a href=\"https:\/\/docs.microsoft.com\/en-us\/dotnet\/csharp\/programming-guide\/statements-expressions-operators\/equality-comparisons#value-equality\" target=\"_blank\" rel=\"noopener\">\u57fa\u4e8e\u503c\u7684\u76f8\u7b49\u6027<\/a>\u3002\u56e0\u6b64\uff0c\u9700\u8981\u5bf9\u6240\u6709\u5c5e\u6027\u6bd4\u8f83\u503c\u7684\u5bf9\u8c61\u901a\u5e38\u53ef\u4ee5\u5f88\u597d\u5730\u8fc1\u79fb\u5230 record \u6216 record struct\u3002\u901a\u5e38\uff0c\u5728\u6d89\u53ca\u5230\u9ad8\u5e76\u53d1\u548c\u5171\u4eab\u6570\u636e\u7684\u7a0b\u5e8f\u4e2d\u4f1a\u51fa\u73b0\u53ef\u53d8\u7c7b\u578b\u76f8\u5173\u95ee\u9898\u3002<\/p>\n\n\n\n<p>Record \u58f0\u660e\u5728\u8bed\u6cd5\u4e0a\u51e0\u4e4e\u4e0e\u7c7b\u5b8c\u5168\u76f8\u540c \u2013 \u552f\u4e00\u533a\u522b\u662f\u5173\u952e\u5b57\u4e0d\u540c\u3002\u8981\u66f4\u65b0\u65e7\u4ee3\u7801\uff0c\u8bf7\u5c06&nbsp;<code>class<\/code>&nbsp;\u5173\u952e\u5b57\u66ff\u6362\u4e3a&nbsp;<code>record<\/code>\uff0c\u5220\u9664\u6784\u9020\u51fd\u6570\uff0c\u5e76\u4ee5\u5185\u8054\u65b9\u5f0f\u521d\u59cb\u5316\u5c5e\u6027\u3002\u4e00\u952e\u5373\u53ef\u5b8c\u6210\u6240\u6709\u64cd\u4f5c\uff1a<kbd>Alt+Enter<\/kbd>\uff08\u8bf7\u786e\u4fdd\u6587\u672c\u5149\u6807\u4f4d\u4e8e\u7c7b\u540d\u4e0a\uff09\u3002\u9009\u62e9&nbsp;<strong>To record<\/strong>\uff08\u8f6c\u6362\u4e3a\u8bb0\u5f55\uff09\u3002Rider \u4f1a\u5904\u7406\u5168\u90e8\u8f6c\u6362\u3002\u73b0\u5728\uff0c\u8be5\u7c7b\u5df2\u91cd\u6784\u4e3a&nbsp;<code>record<\/code>\uff0c\u8bf7\u6ce8\u610f\u6784\u9020\u51fd\u6570\u5df2\u7070\u663e\uff0c\u4ee5\u4fbf\u8f6c\u6362\u4e3a\u4e3b\u6784\u9020\u51fd\u6570\uff08\u968f\u540e\u4ecb\u7ecd\uff09\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-to-record.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-to-record.png\" alt=\"Convert a class to a record\" class=\"wp-image-266169\" width=\"500\"><\/figure>\n\n\n\n<p>C# 9 \u4e2d\u5f15\u5165\u4e86 record\uff0cC# 10 \u4e2d\u5f15\u5165\u4e86 record struct\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e3b\u6784\u9020\u51fd\u6570<\/h2>\n\n\n\n<p>\u968f\u7740 C# \u7684\u9010\u6e10\u6f14\u53d8\uff0c\u4e0e\u4ee5\u524d\u76f8\u6bd4\uff0c\u5b8c\u6210\u76f8\u540c\u4efb\u52a1\u6240\u9700\u7684\u4ee3\u7801\u5df2\u53d8\u5f97\u66f4\u5c11\u3002\u8fd9\u610f\u5473\u7740\u6709\u5f88\u591a\u4e0d\u5fc5\u8981\u7684\u6837\u677f\u4ee3\u7801\u5df2\u6d3e\u4e0d\u4e0a\u7528\u573a\uff0c\u5c06\u6d88\u5931\u5728\u4eba\u4eec\u7684\u89c6\u91ce\u5f53\u4e2d\u3002\u8fd9\u6837\u5f88\u597d\uff0c\u56e0\u4e3a\u90a3\u79cd\u4ee3\u7801\u5f80\u5f80\u4f1a\u9020\u6210\u59a8\u788d\u5e76\u4e14\u5e76\u4e0d\u4f1a\u5e26\u6765\u591a\u5c11\u4e1a\u52a1\u4ef7\u503c\u3002<\/p>\n\n\n\n<p>\u901a\u8fc7\u5c06\u5173\u952e\u5b57&nbsp;<code>class<\/code>&nbsp;\u66f4\u6539\u4e3a&nbsp;<code>record<\/code>&nbsp;\uff08\u6216\u5c06&nbsp;<code>struct<\/code>&nbsp;\u66f4\u6539\u4e3a&nbsp;<code>record struct<\/code>\uff09\u4ece\u7c7b\u8fc1\u79fb\u5230 record \u540e\uff0c\u60a8\u5c31\u4e0d\u518d\u9700\u8981\u6784\u9020\u51fd\u6570\u548c setter\u3002\u6b64\u65f6\uff0c\u60a8\u53ef\u4ee5\u76f4\u63a5\u5c06\u5b83\u5220\u9664\u3002\u4f46\u5982\u679c\u60a8\u9700\u8981\u8bbe\u7f6e\u8fd9\u4e9b\u503c\uff0c\u8bf7\u4f7f\u7528\u4e3b\u6784\u9020\u51fd\u6570\u3002<\/p>\n\n\n\n<p>\u8981\u8fc1\u79fb\u5230\u4e3b\u6784\u9020\u51fd\u6570\uff0c\u8bf7\u5c06\u6587\u672c\u5149\u6807\u653e\u7f6e\u5728\u73b0\u6709\u6784\u9020\u51fd\u6570\u4e0a\uff0c\u6309&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u5e76\u9009\u62e9\u9002\u5f53\u7684&nbsp;<strong>Convert to primary constructor<\/strong>\uff08\u8f6c\u6362\u4e3a\u4e3b\u6784\u9020\u51fd\u6570\uff09\u64cd\u4f5c\u3002\u9009\u62e9\u8981\u66f4\u65b0\u7684\u5185\u5bb9\uff1a\u5f53\u524d\u5bf9\u8c61\u3001\u5f53\u524d\u6587\u4ef6\u3001\u9879\u76ee\u6216\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-primary-ctor.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-primary-ctor.png\" alt=\"Convert to primary constructor\" class=\"wp-image-266059\" width=\"600\"><\/figure>\n\n\n\n<p>\u4e3b\u6784\u9020\u51fd\u6570\u5728 C# 9 \u4e2d\u63a8\u51fa\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u73b0\u4ee3 Switch \u8868\u8fbe\u5f0f<\/h2>\n\n\n\n<p>Switch \u8bed\u53e5\u53ef\u4ee5\u6839\u636e\u4e00\u5217\u503c\u6765\u8bc4\u4f30\u8868\u8fbe\u5f0f\u3002<code>string<\/code>\u3001<code>int<\/code>&nbsp;\u548c&nbsp;<code>enum<\/code>&nbsp;\u7b49\u7c7b\u578b\u662f\u8bc4\u4f30\u4e2d\u901a\u5e38\u4f1a\u4f7f\u7528\u7684\u7c7b\u578b\uff0c\u5b83\u4eec\u5f80\u5f80\u975e\u5e38\u7b80\u5355\u3002\u4f46\u662f\uff0cswitch \u8868\u8fbe\u5f0f\u4f1a\u6839\u636e\u4e00\u5217\u57fa\u4e8e\u6a21\u5f0f\u5339\u914d\u7684\u5019\u9009\u8868\u8fbe\u5f0f\u6765\u8bc4\u4f30\u8868\u8fbe\u5f0f\u3002\u5b83\u53ef\u4ee5\u901a\u8fc7\u4e0d\u540c\u7684\u65b9\u5f0f\u8bc4\u4f30\u66f4\u591a\u8868\u8fbe\u5f0f\uff08\u4f8b\u5982\u4f7f\u7528 lambda\uff09\uff0c\u5e76\u4e14\u6bd4\u4ee5\u524d\u66f4\u52a0\u7075\u6d3b\u3002\u5e76\u975e\u6240\u6709 switch \u8bed\u53e5\u90fd\u6700\u9002\u4e8e\u4f5c\u4e3a switch \u8868\u8fbe\u5f0f\uff0c\u4f46\u4ec5\u4ec5\u662f\u56e0\u4e3a\u4e00\u4e9b\u5f00\u53d1\u8005\u559c\u6b22\u66f4\u77ed\u3001\u66f4\u7b80\u6d01\u7684\u8bed\u6cd5\uff0c\u4fbf\u8db3\u591f\u503c\u5f97\u5347\u7ea7\u3002<\/p>\n\n\n\n<p>\u5728\u6587\u672c\u5149\u6807\u4f4d\u4e8e&nbsp;<code>switch<\/code>&nbsp;\u5173\u952e\u5b57\u4e0a\u65f6\u6309&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u5c06 switch \u8bed\u53e5\u8f6c\u6362\u4e3a switch \u8868\u8fbe\u5f0f\uff0c\u7136\u540e\u9009\u62e9\u8f6c\u6362\u9009\u9879\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-switch-expression.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-switch-expression.png\" alt=\"Upgrade from switch statement to switch expression\" class=\"wp-image-266081\" width=\"800\"><\/figure>\n\n\n\n<p>C# 8 \u4e2d\u91c7\u53d6\u4e86\u8fd9\u4e00\u8f6c\u53d8\uff0c\u4e3a\u6211\u4eec\u5e26\u6765\u4e86 switch \u8868\u8fbe\u5f0f\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u53ef\u7a7a\u5f15\u7528\u7c7b\u578b<\/h2>\n\n\n\n<p>\u5728\u5305\u62ec\u65e9\u671f\u7248\u672c C# \u5728\u5185\u7684\u8bb8\u591a\u8bed\u8a00\u4e2d\uff0c\u60a8\u90fd\u9700\u8981\u5728\u4ee3\u7801\u4e2d\u7f16\u5199 null \u68c0\u67e5\u3002\u5728\u8bb8\u591a\u5708\u5b50\u91cc\uff0c\u5c3d\u804c\u5c3d\u8d23\u5730\u68c0\u67e5 null \u90fd\u4f1a\u88ab\u8ba4\u4e3a\u662f\u4e00\u79cd\u201c\u4f18\u79c0\u7684\u9632\u5fa1\u6027\u7f16\u7a0b\u201d\u3002\u4f46\u8fd9\u4e00\u884c\u4e3a\u5df2\u7ecf\u53ef\u4ee5\u9000\u51fa\u821e\u53f0\u3002\u5728 2022 \u5e74\u7684\u5f53\u4e0b\uff0c\u7f16\u8bd1\u5668\u548c\u5de5\u5177\u5df2\u7ecf\u53ef\u4ee5\u8f7b\u677e\u5730\u4e3a\u6211\u4eec\u5b8c\u6210\u8fd9\u4e9b\u68c0\u67e5\u3002\u7f16\u7a0b\u8bed\u8a00\u5e94\u4f7f\u5f00\u53d1\u8005\u80fd\u591f\u4e13\u6ce8\u4e8e\u89e3\u51b3\u4e1a\u52a1\u95ee\u9898\uff0c\u8fd9\u662f\u5e94\u7528\u7a0b\u5e8f\u5f00\u53d1\u65b9\u9762\u7684\u5171\u540c\u4e3b\u9898\u3002\u5426\u5219\uff0c\u5f00\u53d1\u8005\u4eec\u9700\u8981\u82b1\u8d39\u5927\u91cf\u65f6\u95f4\u6765\u91cd\u65b0\u521b\u5efa\u6216\u4fee\u6b63\u5e38\u89c1\u7684\u6280\u672f\u573a\u666f\uff0c\u5305\u62ec\u8017\u65f6\u5730\u8fdb\u884c\u672c\u4f8b\u4e2d\u7684 null \u68c0\u67e5\u3002<\/p>\n\n\n\n<p>\u867d\u7136\u5728\u66f4\u65b0\u4ee3\u7801\u65f6\u6709\u8bb8\u591a\u53ef\u4ee5\u8003\u8651\u7684\u53ef\u7a7a\u6027\u68c0\u67e5\u65b9\u6cd5\uff0c\u4f46\u6709\u4e9b\u5feb\u901f\u4fee\u590d\u4f1a\u975e\u5e38\u65b9\u4fbf\u4e14\u6613\u4e8e\u4e0a\u624b\u3002\u4f8b\u5982\uff0c\u60a8\u53ef\u80fd\u5728\u91cd\u6784\u671f\u95f4\u5bf9\u6784\u9020\u51fd\u6570\u4e2d\u7684\u5b9e\u53c2\u5e94\u7528\u4e86&nbsp;<code>?<\/code>&nbsp;\u5b57\u7b26\u4ee5\u8868\u793a\u53ef\u7a7a\u6027\uff0c\u4f46\u5fd8\u8bb0\u5c06\u5176\u5e94\u7528\u4e8e\u76f8\u5e94\u7684\u5c5e\u6027\u3002\u4e0d\u7528\u62c5\u5fc3\uff0c\u60a8\u4f1a\u770b\u5230\u4e00\u4e2a\u6307\u793a\u5668\uff0c\u63d0\u9192\u60a8\u5728\u7f16\u8f91\u5668\u4e2d\u8fdb\u884c\u5fc5\u8981\u7684\u66f4\u65b0\u3002\u6309&nbsp;<kbd>Alt+Enter<\/kbd>&nbsp;\u9009\u62e9\u8981\u6267\u884c\u7684\u64cd\u4f5c\u3002\u5728\u6b64\u793a\u4f8b\u4e2d\uff0c\u5c06\u8be5\u5c5e\u6027\u8bbe\u7f6e\u4e3a\u53ef\u7a7a\u4ee5\u5b8c\u5584\u6784\u9020\u51fd\u6570\u7684\u5b9e\u53c2\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" data-gif-src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-nullable-type.gif\" src=\"https:\/\/blog.jetbrains.com\/wp-content\/uploads\/2022\/07\/EVAN-10908-nullable-type.png\" alt=\"Top level statements\" class=\"wp-image-266103\" width=\"800\"><\/figure>\n\n\n\n<p>\u540c\u65f6\uff0c\u8bf7\u9605\u8bfb\u6709\u5173<a href=\"https:\/\/blog.maartenballiauw.be\/post\/2022\/04\/11\/nullable-reference-types-in-csharp-migrating-to-nullable-reference-types-part-1.html\" target=\"_blank\" rel=\"noopener\">\u8fc1\u79fb\u5230\u53ef\u7a7a\u5f15\u7528\u7c7b\u578b<\/a>\u3001<a href=\"https:\/\/blog.maartenballiauw.be\/post\/2022\/04\/19\/internals-of-csharp-nullable-reference-types-migrating-to-nullable-reference-types-part-2.html\" target=\"_blank\" rel=\"noopener\">\u5b83\u4eec\u7684\u5e55\u540e\u8fd0\u4f5c\u65b9\u5f0f<\/a>\u4ee5\u53ca\u5982\u4f55<a href=\"https:\/\/blog.jetbrains.com\/dotnet\/2020\/04\/20\/nullable-reference-types-migration\/\">\u5347\u7ea7\u4ee3\u7801\u4ee5\u4f7f\u7528\u53ef\u7a7a\u5f15\u7528\u7c7b\u578b<\/a>\u7684\u66f4\u591a\u5185\u5bb9\u3002<\/p>\n\n\n\n<p>\u53ef\u7a7a\u5f15\u7528\u7c7b\u578b\u59cb\u4e8e C# 9\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u7ed3\u8bba<\/h2>\n\n\n\n<p>\u8fd9\u7bc7\u535a\u6587\u5411\u60a8\u5c55\u793a\u4e86\u5982\u4f55\u501f\u52a9\u8bf8\u5982 ReSharper \u548c Rider \u7b49\u5de5\u5177\u6765\u91cd\u6784\u4ee3\u7801\u4ee5\u5b9e\u73b0\u73b0\u4ee3\u5316\u3002<strong>\u867d\u4e0d\u5fc5\u4e00\u76f4\u4f7f\u7528\u8bed\u8a00\u7684\u6700\u65b0\u7248\u672c\uff0c\u4f46\u6709\u5fc5\u8981\u91cd\u6784\u4ee3\u7801\u4ee5\u4f7f\u5176\u66f4\u5177\u53ef\u8bfb\u6027\u548c\u6548\u7387<\/strong>\u3002\u8fd9\u610f\u5473\u7740\u9700\u8981\u9002\u65f6\u8fdb\u884c\u66f4\u65b0\u3002\u4f18\u79c0\u7684\u5de5\u5177\u53ef\u4ee5\u5e2e\u52a9\u91cd\u6784\u548c\u66f4\u65b0\u65e7\u4ee3\u7801\u3001\u8fc1\u79fb\u548c\u73b0\u4ee3\u5316\u4ee3\u7801\u5e93\u3002\u8bf7<a href=\"https:\/\/www.jetbrains.com.cn\/dotnet\/\" target=\"_blank\" rel=\"noopener\">\u67e5\u770b\u6211\u4eec\u7684 .NET \u5de5\u5177<\/a>\uff0c\u5e76\u544a\u8bc9\u6211\u4eec\u60a8\u8ba1\u5212\u5982\u4f55\u5bf9\u4ee3\u7801\u8fdb\u884c\u73b0\u4ee3\u5316\u6539\u9020\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>\u672c\u535a\u6587\u82f1\u6587\u539f\u4f5c\u8005\uff1a<\/p>\n\n\n    <div class=\"about-author \">\n        <div class=\"about-author__box\">\n            <div class=\"row\">\n                <div class=\"about-author__box-img\">\n                    <img decoding=\"async\" src=\"https:\/\/secure.gravatar.com\/avatar\/?s=200&#038;r=g\" width=\"200\" height=\"200\" alt=\"\" loading=\"lazy\"  class=\"avatar avatar-200 wp-user-avatar wp-user-avatar-200 photo avatar-default\">\n                <\/div>\n                <div class=\"about-author__box-text\">\n                                                        <\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n","protected":false},"author":1297,"featured_media":266337,"comment_status":"closed","ping_status":"closed","template":"","categories":[4992,1401],"tags":[158,211,6766,6306,2085,195],"cross-post-tag":[],"acf":[],"_links":{"self":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/dotnet\/278976"}],"collection":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/dotnet"}],"about":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/types\/dotnet"}],"author":[{"embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/users\/1297"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/comments?post=278976"}],"version-history":[{"count":10,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/dotnet\/278976\/revisions"}],"predecessor-version":[{"id":279005,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/dotnet\/278976\/revisions\/279005"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/media\/266337"}],"wp:attachment":[{"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/media?parent=278976"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/categories?post=278976"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/tags?post=278976"},{"taxonomy":"cross-post-tag","embeddable":true,"href":"https:\/\/blog.jetbrains.com\/zh-hans\/wp-json\/wp\/v2\/cross-post-tag?post=278976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}