{"id":3547,"date":"2025-04-19T09:50:35","date_gmt":"2025-04-19T01:50:35","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=3547"},"modified":"2025-04-19T09:50:35","modified_gmt":"2025-04-19T01:50:35","slug":"c-%e7%89%b9%e6%80%a7%ef%bc%88attribute%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/04\/19\/c-%e7%89%b9%e6%80%a7%ef%bc%88attribute%ef%bc%89\/","title":{"rendered":"C# \u7279\u6027\uff08Attribute\uff09"},"content":{"rendered":"\n

\u672c\u7ae0\u8282\u56f4\u7ed5\u4ee5\u4e0b\u4e03\u4e2a\u65b9\u9762\u6765\u7cfb\u7edf\u8bb2\u89e3C# \u7684\u7279\u6027\uff08Attribute\uff09<\/strong>\uff0c\u80fd\u591f\u5168\u9762\u6df1\u5165\u4e86\u89e3 C# \u7684\u7279\u6027\uff08Attribute\uff09<\/strong>\u3002<\/p>\n\n\n\n

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\u4e00\u3001\u4ec0\u4e48\u662f Attribute\uff08\u7279\u6027\uff09\uff1f<\/h2>\n\n\n\n

\u5728 C# \u4e2d\uff0c\u7279\u6027\uff08Attribute\uff09<\/strong> \u662f\u4e00\u79cd\u7528\u4e8e\u5411\u7a0b\u5e8f\u7684\u5143\u7d20\uff08\u5982\u7c7b\u3001\u65b9\u6cd5\u3001\u5c5e\u6027\u3001\u5b57\u6bb5\u7b49\uff09\u6dfb\u52a0\u5143\u6570\u636e\u7684\u673a\u5236\u3002<\/p>\n\n\n\n

\u5b83\u4e0d\u4f1a\u76f4\u63a5\u5f71\u54cd\u7a0b\u5e8f\u8fd0\u884c\u903b\u8f91\uff0c\u800c\u662f\u53ef\u4ee5\u901a\u8fc7 \u53cd\u5c04<\/strong> \u5728\u8fd0\u884c\u65f6\u8bfb\u53d6\uff0c\u7528\u4e8e\u63a7\u5236\u884c\u4e3a\u3001\u914d\u7f6e\u4fe1\u606f\u3001\u5b9e\u73b0\u6846\u67b6\u652f\u6301\u7b49\u3002<\/p>\n\n\n\n

\n

\u7b80\u5355\u8bf4\uff1aAttribute \u662f\u544a\u8bc9\u7a0b\u5e8f\u201c\u8fd9\u662f\u4e00\u4e9b\u989d\u5916\u7684\u4fe1\u606f\u201d\uff0c\u4f9b\u8fd0\u884c\u65f6\u6216\u6846\u67b6\u4f7f\u7528\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n

\ud83d\udcd8 \u5b98\u65b9\u6587\u6863<\/strong>\uff1a
https:\/\/learn.microsoft.com\/zh-cn\/dotnet\/csharp\/programming-guide\/concepts\/attributes\/<\/p>\n\n\n\n

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\u4e8c\u3001Attribute \u7684\u4f7f\u7528\u573a\u666f<\/h2>\n\n\n\n
\u573a\u666f<\/th>\u8bf4\u660e<\/th><\/tr><\/thead>
\u6807\u6ce8\u5e8f\u5217\u5316\u89c4\u5219<\/td>\u5982 [JsonProperty(\"name\")]<\/code> \u63a7\u5236\u5e8f\u5217\u5316\u5b57\u6bb5<\/td><\/tr>
\u63a7\u5236\u53cd\u5c04\u884c\u4e3a<\/td>\u63a7\u5236\u662f\u5426\u53c2\u4e0e\u53cd\u5c04\u3001\u6807\u8bc6\u65b9\u6cd5\u7528\u9014<\/td><\/tr>
\u58f0\u660e\u6027\u7f16\u7a0b<\/td>\u6bd4\u5982 [Obsolete]<\/code> \u6807\u8bb0\u65b9\u6cd5\u8fc7\u65f6<\/td><\/tr>
ASP.NET \u914d\u7f6e<\/td>\u5982 [HttpGet]<\/code>\u3001[Route(\"api\/test\")]<\/code><\/td><\/tr>
\u81ea\u5b9a\u4e49\u9a8c\u8bc1<\/td>\u8868\u5355\u6a21\u578b\u9a8c\u8bc1 [Required]<\/code>, [MaxLength]<\/code> \u7b49<\/td><\/tr>
\u5355\u5143\u6d4b\u8bd5<\/td>\u5982 [TestMethod]<\/code>, [Fact]<\/code>, [Theory]<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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\u4e09\u3001Attribute \u7684\u8bed\u6cd5\u57fa\u7840<\/h2>\n\n\n\n

\u2705 \u4f7f\u7528\u7cfb\u7edf\u5185\u7f6e Attribute<\/h3>\n\n\n\n
[Obsolete(\"\u8bf7\u4e0d\u8981\u518d\u4f7f\u7528\u8fd9\u4e2a\u65b9\u6cd5\")]\npublic void OldMethod()\n{\n    \/\/ \u65e7\u903b\u8f91\n}<\/code><\/pre>\n\n\n\n
\ud83d\udd0d ObsoleteAttribute<\/code> \u4f1a\u5728\u7f16\u8bd1\u65f6\u53d1\u51fa\u8b66\u544a\/\u9519\u8bef\u3002<\/p>\n\n\n\n
\u2705 \u7279\u6027\u57fa\u672c\u8bed\u6cd5\u7ed3\u6784<\/h3>\n\n\n\n
[AttributeName(positional_argument, named_argument=value)]<\/code><\/pre>\n\n\n\n
\u547d\u540d\u89c4\u8303\u662f\uff1a\u7279\u6027\u7c7b\u4ee5 Attribute<\/code> \u7ed3\u5c3e\uff0c\u4f46\u4f7f\u7528\u65f6\u53ef\u4ee5\u7701\u7565\u3002<\/p>\n\n\n\n
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\u56db\u3001\u81ea\u5b9a\u4e49 Attribute<\/h2>\n\n\n\n
1. \u5b9a\u4e49\u7279\u6027\u7c7b<\/h3>\n\n\n\n
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]\npublic class MyNoteAttribute : Attribute\n{\n    public string Note { get; }\n\n    public MyNoteAttribute(string note)\n    {\n        Note = note;\n    }\n}<\/code><\/pre>\n\n\n\n
2. \u5e94\u7528\u7279\u6027<\/h3>\n\n\n\n
[MyNote(\"\u8fd9\u4e2a\u7c7b\u7528\u4e8e\u6f14\u793a\")]\npublic class DemoClass\n{\n    [MyNote(\"\u8c03\u7528\u524d\u8bf7\u9a8c\u8bc1\")]\n    public void DoSomething() { }\n}<\/code><\/pre>\n\n\n\n
3. \u4f7f\u7528\u53cd\u5c04\u8bfb\u53d6\u7279\u6027<\/h3>\n\n\n\n
var type = typeof(DemoClass);\nvar attributes = type.GetCustomAttributes(typeof(MyNoteAttribute), false);\n\nforeach (MyNoteAttribute attr in attributes)\n{\n    Console.WriteLine(attr.Note);\n}<\/code><\/pre>\n\n\n\n
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\u4e94\u3001\u5b9e\u6218\u6848\u4f8b\uff1a\u57fa\u4e8e\u7279\u6027 + \u53cd\u5c04\u5b9e\u73b0\u63a5\u53e3\u6743\u9650\u63a7\u5236<\/h2>\n\n\n\n
\u573a\u666f\uff1a\u6211\u4eec\u4e3a API \u65b9\u6cd5\u6807\u8bb0\u89d2\u8272\u6743\u9650\u7279\u6027\uff0c\u5e76\u5728\u6267\u884c\u524d\u6821\u9a8c\u3002<\/h3>\n\n\n\n
\u2705 1. \u5b9a\u4e49\u7279\u6027\u7c7b<\/h4>\n\n\n\n
[AttributeUsage(AttributeTargets.Method)]\npublic class RoleAttribute : Attribute\n{\n    public string RequiredRole { get; }\n\n    public RoleAttribute(string role)\n    {\n        RequiredRole = role;\n    }\n}<\/code><\/pre>\n\n\n\n
\u2705 2. \u5728\u65b9\u6cd5\u4e2d\u6807\u6ce8<\/h4>\n\n\n\n
public class UserController\n{\n    [Role(\"Admin\")]\n    public void DeleteUser() { }\n\n    [Role(\"User\")]\n    public void ViewProfile() { }\n}<\/code><\/pre>\n\n\n\n
\u2705 3. \u8fd0\u884c\u65f6\u5224\u65ad\u6743\u9650<\/h4>\n\n\n\n
public void ExecuteWithRoleCheck(string methodName, string userRole)\n{\n    var method = typeof(UserController).GetMethod(methodName);\n    var attr = method.GetCustomAttribute<RoleAttribute>();\n\n    if (attr != null && attr.RequiredRole != userRole)\n    {\n        throw new UnauthorizedAccessException(\"\u6743\u9650\u4e0d\u8db3\");\n    }\n\n    method.Invoke(new UserController(), null);\n}<\/code><\/pre>\n\n\n\n
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\u516d\u3001\u5e38\u7528\u7cfb\u7edf\u5185\u7f6e Attribute<\/h2>\n\n\n\n
\u7279\u6027<\/th>\u8bf4\u660e<\/th><\/tr><\/thead>
[Obsolete]<\/code><\/td>\u6807\u8bb0\u4e0d\u63a8\u8350\u4f7f\u7528\u7684\u65b9\u6cd5<\/td><\/tr>
[Serializable]<\/code><\/td>\u6807\u8bb0\u53ef\u4ee5\u5e8f\u5217\u5316\u7684\u7c7b<\/td><\/tr>
[NonSerialized]<\/code><\/td>\u6807\u8bb0\u5b57\u6bb5\u4e0d\u53c2\u4e0e\u5e8f\u5217\u5316<\/td><\/tr>
[DllImport]<\/code><\/td>\u7528\u4e8e\u8c03\u7528\u975e\u6258\u7ba1 DLL<\/td><\/tr>
[Conditional]<\/code><\/td>\u6839\u636e\u6761\u4ef6\u7f16\u8bd1<\/td><\/tr>
[DefaultValue]<\/code><\/td>\u8bbe\u7f6e\u9ed8\u8ba4\u503c<\/td><\/tr>
[Description]<\/code><\/td>\u6dfb\u52a0\u63cf\u8ff0\u4fe1\u606f\uff0c\u5e38\u7528\u4e8e UI \u6216\u914d\u7f6e<\/td><\/tr>
[Required]<\/code>, [Range]<\/code><\/td>ASP.NET \u8868\u5355\u9a8c\u8bc1\u7279\u6027<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\ud83d\udc49 \u8be6\u89c1\u5b98\u65b9\u6587\u6863\uff1ahttps:\/\/learn.microsoft.com\/zh-cn\/dotnet\/standard\/attributes\/<\/p>\n\n\n\n
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\u4e03\u3001\u6700\u4f73\u5b9e\u8df5\u4e0e\u6ce8\u610f\u4e8b\u9879<\/h2>\n\n\n\n
    \n
  1. \u4e0d\u8981\u6ee5\u7528\u7279\u6027<\/strong>\uff1a\u4ec5\u5728\u9700\u8981\u8868\u8fbe\u5143\u4fe1\u606f\u6216\u8fd0\u884c\u65f6\u52a8\u6001\u5904\u7406\u7684\u60c5\u51b5\u4e0b\u4f7f\u7528\u3002<\/li>\n\n\n\n
  2. \u5408\u7406\u4f7f\u7528 AttributeUsage<\/strong> \u63a7\u5236\u7279\u6027\u5e94\u7528\u8303\u56f4\uff1a<\/li>\n<\/ol>\n\n\n\n
       [AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]<\/code><\/pre>\n\n\n\n
      \n
    1. \u7ed3\u5408\u53cd\u5c04\u8c28\u614e\u5904\u7406\u6027\u80fd\u95ee\u9898<\/strong>\uff0c\u5c24\u5176\u662f\u5728\u5faa\u73af\u4f53\u4e2d\u9891\u7e41\u53cd\u5c04\u3002<\/li>\n\n\n\n
    2. \u591a\u7528\u4e8e\u58f0\u660e\u6027\u7f16\u7a0b\u548c\u5143\u6570\u636e\u9a71\u52a8\u7684\u6846\u67b6\uff08\u5982 ASP.NET\u3001EF Core\u3001XUnit\uff09<\/strong>\u3002<\/li>\n<\/ol>\n\n\n\n
      \n\n\n\n
      \u76f8\u5173\u6743\u5a01\u53c2\u8003\u94fe\u63a5<\/h2>\n\n\n\n