{"id":278,"date":"2022-06-28T18:38:52","date_gmt":"2022-06-28T10:38:52","guid":{"rendered":"https:\/\/www.fengjijiao.cn\/?p=278"},"modified":"2022-06-29T14:44:32","modified_gmt":"2022-06-29T06:44:32","slug":"csharp%e7%89%b9%e6%80%a7%ef%bc%88attribute%ef%bc%89%e5%8f%8d%e5%b0%84%ef%bc%88reflection%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.fengjijiao.cn\/?p=278","title":{"rendered":"C#\u7279\u6027\uff08Attribute\uff09&#038;\u53cd\u5c04\uff08Reflection\uff09"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code>#define DEBUG_MODE\r\nusing System;\r\nusing System.Reflection;\r\nusing System.Diagnostics;\r\n\r\nnamespace ConsoleApp1\r\n{\r\n    class Program\r\n    {\r\n        static void Main(string&#91;] args)\r\n        {\r\n            \/\/C# \u7279\u6027(Attribute)\r\n            \/*\r\n             * \u7279\u6027(Attribute)\u662f\u7528\u4e8e\u5728\u8fd0\u884c\u65f6\u4f20\u9012\u7a0b\u5e8f\u4e2d\u7684\u5404\u79cd\u5143\u7d20\uff08\u6bd4\u5982\u7c7b\u3001\u65b9\u6cd5\u3001\u7ed3\u6784\u3001\u679a\u4e3e\u3001\u7ec4\u4ef6\u7b49\uff09\u7684\u884c\u4e3a\u4fe1\u606f\u7684\u58f0\u660e\u6027\u6807\u7b7e\u3002\u60a8\u53ef\u4ee5\u901a\u8fc7\u4f7f\u7528\u7279\u6027\u5411\u7a0b\u5e8f\u6dfb\u52a0\u58f0\u660e\u6027\u4fe1\u606f\u3002\u4e00\u4e2a\u58f0\u660e\u6027\u6807\u7b7e\u662f\u901a\u8fc7\u653e\u7f6e\u5728\u5b83\u6240\u5e94\u7528\u7684\u5143\u7d20\u524d\u9762\u7684\u65b9\u62ec\u53f7(&#91;])\u6765\u63cf\u8ff0\u7684\u3002\r\n             * \u7279\u6027(Attribute)\u7528\u4e8e\u6dfb\u52a0\u5143\u6570\u636e\uff0c\u5982\u7f16\u8bd1\u5668\u6307\u4ee4\u548c\u6ce8\u91ca\u3001\u63cf\u8ff0\u3001\u65b9\u6cd5\u3001\u7c7b\u7b49\u5176\u4ed6\u4fe1\u606f\u3002.Net\u6846\u67b6\u63d0\u4f9b\u4e86\u4e24\u79cd\u7c7b\u578b\u7684\u7279\u6027\uff1a\u9884\u5b9a\u4e49\u7279\u6027\u548c\u81ea\u5b9a\u4e49\u7279\u6027\r\n             * \r\n             * \u89c4\u5b9a\u7279\u6027(Attribute)\r\n             * \u8bed\u6cd5\uff1a&#91;attribute(positional_parameters, name_parameter = value, ...)] element\r\n             * positional_parameters\u89c4\u5b9a\u5fc5\u987b\u7684\u4fe1\u606f\r\n             * name_parameter\u89c4\u5b9a\u53ef\u9009\u7684\u4fe1\u606f\r\n             * \r\n             * \u9884\u5b9a\u4e49\u7279\u6027(Attribute)\r\n             * .Net\u6846\u67b6\u63d0\u4f9b\u4e86\u4e09\u79cd\u9884\u5b9a\u4e49\u7279\u6027\uff1a\r\n             * 1.AttributeUsage\r\n             * 2.Conditional\r\n             * 3.Obsolete\r\n             * \r\n             * AttributeUsage:\u63cf\u8ff0\u4e86\u5982\u4f55\u4f7f\u7528\u4e00\u4e2a\u81ea\u5b9a\u4e49\u7279\u6027\u7c7b\u3002\u5b83\u89c4\u5b9a\u4e86\u7279\u6027\u53ef\u5e94\u7528\u5230\u7684\u9879\u76ee\u7684\u7c7b\u578b\u3002\r\n             * &#91;AttributeUsage(\r\n             *     validon,\r\n             *     AllowMultiple allowmultiple,\r\n             *     Inherited inherited\r\n             * )]\r\n             * \u5176\u4e2d\uff1a\r\n             * validon\u89c4\u5b9a\u7279\u6027\u53ef\u88ab\u653e\u7f6e\u7684\u8bed\u8a00\u5143\u7d20\u3002\u5b83\u662f\u679a\u4e3e\u5668AttributeTargets\u7684\u503c\u7684\u7ec4\u5408\u3002\u9ed8\u8ba4\u662fAttributeTargets.All\r\n             * allowmultiple(\u53ef\u9009\u7684)\u4e3a\u8be5\u7279\u6027\u7684AllowMultiple\u5c5e\u6027(property)\u63d0\u4f9b\u4e00\u4e2a\u5e03\u5c14\u503c\u3002\u5982\u679c\u4e3atrue\uff0c\u5219\u8be5\u7279\u6027\u662f\u591a\u7528\u7684\u3002\u9ed8\u8ba4\u503c\u662ffalse\uff08\u5355\u7528\u7684\uff09\u3002\r\n             * inherited\uff08\u53ef\u9009\u7684\uff09\u4e3a\u8be5\u7279\u6027\u7684Inherited\u5c5e\u6027(property)\u63d0\u4f9b\u4e00\u4e2a\u5e03\u5c14\u503c\u3002\u5982\u679c\u4e3atrue\uff0c\u5219\u8be5\u7279\u6027\u53ef\u4ee5\u88ab\u6d3e\u751f\u7c7b\u7ee7\u627f\u3002\u9ed8\u8ba4\u503c\u4e3afalse\uff08\u4e0d\u88ab\u7ee7\u627f\uff09\u3002\r\n             * \r\n             * \u4f8b\u5982:\r\n             * &#91;AttributeUsage(AttributeTargets.Class |\r\n             *  AttributeTargets.Constructor |\r\n             *  AttributeTargets.Field |\r\n             *  AttributeTargets.Method |\r\n             *  AttributeTargets.Property,\r\n             *  AllowMultiple = true)]\r\n             *  \r\n             *  Conditional\r\n             *  \u8fd9\u4e2a\u9884\u5b9a\u4e49\u7279\u6027\u6807\u6ce8\u4e86\u4e00\u4e2a\u6761\u4ef6\u65b9\u6cd5\uff0c\u5176\u6267\u884c\u4f9d\u8d56\u4e8e\u6307\u5b9a\u7684\u9884\u5904\u7406\u6807\u8bc6\u7b26\r\n             *  \u4ed6\u4f1a\u5f15\u8d77\u65b9\u6cd5\u8c03\u7528\u7684\u6761\u4ef6\u7f16\u8bd1\uff0c\u53d6\u51b3\u4e8e\u6307\u5b9a\u503c\uff0c\u6bd4\u5982Debug\u6216Trace\u3002\u4f8b\u5982\uff0c\u5f53\u8c03\u8bd5\u4ee3\u7801\u65f6\u663e\u793a\u53d8\u91cf\u7684\u503c\u3002\r\n             *  \u8bed\u6cd5\uff1a\r\n             *  &#91;Conditional(\r\n             *      conditionalSymbol\r\n             *  )]\r\n             *  \u4f8b\u5982\uff1a\r\n             *  &#91;Conditional(\"DEBUG\")]\r\n             *\/\r\n            \/\/\u5b9e\u4f8b\r\n            MyClass.Message(\"in main func\");\r\n            func1();\r\n\r\n            \/\/Obsolete\r\n            \/\/\u8fd9\u4e2a\u9884\u5b9a\u4e49\u7279\u6027\u6807\u8bb0\u4e86\u4e0d\u5e94\u88ab\u4f7f\u7528\u7684\u7a0b\u5e8f\u5b9e\u4f53\u3002\u5b83\u53ef\u4ee5\u8ba9\u60a8\u901a\u77e5\u7f16\u8f91\u5668\u4e22\u5f03\u67d0\u4e2a\u7279\u5b9a\u7684\u76ee\u6807\u5143\u7d20\u3002\u4f8b\u5982\uff1a\u5f53\u4e00\u4e2a\u65b0\u65b9\u6cd5\u88ab\u7528\u5728\u4e00\u4e2a\u7c7b\u4e2d\uff0c\u4f46\u662f\u60a8\u4ecd\u7136\u60f3\u8981\u4fdd\u6301\u7c7b\u4e2d\u7684\u65e7\u65b9\u6cd5\uff0c\u60a8\u53ef\u4ee5\u901a\u8fc7\u663e\u793a\u4e00\u4e2a\u5e94\u8be5\u4f7f\u7528\u65b0\u65b9\u6cd5\uff0c\u800c\u4e0d\u662f\u65e7\u65b9\u6cd5\u7684\u6d88\u606f\uff0c\u6765\u628a\u5b83\u6807\u8bb0\u4e3aobsolete\uff08\u8fc7\u65f6\u7684\uff09\r\n            \/*\u8bed\u6cd5:\r\n             * &#91;Obsolete(\r\n             *     message\r\n             * )]\r\n             * &#91;Obsolete(\r\n             *     message,\r\n             *     iserror\r\n             * )]\r\n             * \u5176\u4e2d:\r\n             * message\u662f\u4e00\u4e2a\u5b57\u7b26\u4e32\uff0c\u63cf\u8ff0\u9879\u76ee\u4e3a\u4ec0\u4e48\u8fc7\u65f6\u4ee5\u53ca\u8be5\u66ff\u4ee3\u4f7f\u7528\u4ec0\u4e48\r\n             * iserror\u662f\u4e00\u4e2a\u5e03\u5c14\u503c\uff0c\u5982\u679c\u8be5\u503c\u4e3atrue\uff0c\u7f16\u8bd1\u5668\u5e94\u628a\u8be5\u9879\u76ee\u7684\u4f7f\u7528\u5f53\u4f5c\u4e00\u4e2a\u9519\u8bef\u3002\u9ed8\u8ba4\u503cfalse(\u7f16\u8bd1\u5668\u751f\u6210\u4e00\u4e2a\u8b66\u544a)\r\n             *\/\r\n            \/\/\u5b9e\u4f8b\r\n            \/\/OldMethod();\r\n\r\n            \/\/\u521b\u5efa\u81ea\u5b9a\u4e49\u7279\u6027(Attribute)\r\n            \/*\r\n             * .net\u6846\u67b6\u5141\u8bb8\u521b\u5efa\u81ea\u5b9a\u4e49\u7279\u6027\uff0c\u7528\u4e8e\u5b58\u50a8\u58f0\u660e\u6027\u7684\u4fe1\u606f\uff0c\u4e14\u53ef\u5728\u8fd0\u884c\u65f6\u88ab\u68c0\u7d22\u3002\u8be5\u4fe1\u606f\u6839\u636e\u8bbe\u8ba1\u6807\u51c6\u548c\u5e94\u7528\u7a0b\u5e8f\u9700\u8981\uff0c\u53ef\u4e0e\u4efb\u4f55\u76ee\u6807\u5143\u7d20\u76f8\u5173\r\n             * \u521b\u5efa\u5e76\u4f7f\u7528\u81ea\u5b9a\u4e49\u7279\u6027\u5305\u542b\u56db\u4e2a\u6b65\u9aa4\r\n             * \u58f0\u660e\u81ea\u5b9a\u4e49\u7279\u6027->\u6784\u5efa\u81ea\u5b9a\u4e49\u7279\u6027->\u5728\u76ee\u6807\u7a0b\u5e8f\u5143\u7d20\u4e0a\u5e94\u7528\u81ea\u5b9a\u4e49\u7279\u6027->\u901a\u8fc7\u53cd\u5c04\u8bbf\u95ee\u7279\u6027\r\n             * \u6700\u540e\u4e00\u4e2a\u6b65\u9aa4\u662f\u7f16\u5199\u7a0b\u5e8f\u6765\u8bfb\u53d6\u5143\u6570\u636e\u4ee5\u67e5\u627e\u5404\u79cd\u7b26\u53f7\u3002\u5143\u6570\u636e\u662f\u7528\u4e8e\u63cf\u8ff0\u5176\u4ed6\u6570\u636e\u7684\u6570\u636e\u548c\u4fe1\u606f\u3002\u8be5\u7a0b\u5e8f\u5e94\u4f7f\u7528\u53cd\u5c04\u6765\u5728\u8fd0\u884c\u65f6\u8bbf\u95ee\u7279\u6027\u3002\r\n             * \r\n             * \u58f0\u660e\u81ea\u5b9a\u4e49\u7279\u6027\r\n             * \u4e00\u4e2a\u65b0\u7684\u81ea\u5b9a\u4e49\u7279\u6027\u5e94\u6d3e\u751f\u81eaSystem.Attribute\u7c7b\r\n             * \/\/\u4e00\u4e2a\u81ea\u5b9a\u4e49\u7279\u6027BugFix\u88ab\u8d4b\u7ed9\u7c7b\u53ca\u5176\u6210\u5458\r\n             * &#91;AttributeUsage(AttributeTargets.Class |\r\n             * AttributeTargets.Constructor |\r\n             * AttributeTargets.Field |\r\n             * AttributeTargets.Method |\r\n             * AttributeTargets.Property,\r\n             * AllowMultiple = true\r\n             * )]\r\n             * public class DeBugInfo: System.Attribute\r\n             * \r\n             * \u6784\u5efa\u81ea\u5b9a\u4e49\u7279\u6027\r\n             * \u8be5\u7279\u6027\u5c06\u5b58\u50a8\u8c03\u8bd5\u7a0b\u5e8f\u83b7\u5f97\u7684\u4fe1\u606f\uff0c\u5b83\u5b58\u50a8\u4ee5\u4e0b\u4fe1\u606f:\r\n             * bug\u7684\u4ee3\u7801\u7f16\u53f7\r\n             * \u8fa8\u8ba4\u8be5bug\u7684\u5f00\u53d1\u4eba\u5458\u540d\u5b57\r\n             * \u6700\u540e\u4e00\u6b21\u5ba1\u67e5\u8be5\u4ee3\u7801\u7684\u65e5\u671f\r\n             * \u4e00\u4e2a\u5b58\u50a8\u4e86\u5f00\u53d1\u4eba\u5458\u6807\u8bb0\u7684\u5b57\u7b26\u4e32\u6d88\u606f\r\n             * \r\n             * \u6211\u4eec\u7684DeBugInfo\u7c7b\u5c06\u5e26\u67093\u4e2a\u7528\u4e8e\u5b58\u50a8\u524d3\u4e2a\u4fe1\u606f\u7684\u79c1\u6709\u5c5e\u6027(property)\u548c\u4e00\u4e2a\u7528\u4e8e\u5b58\u50a8\u6d88\u606f\u7684\u516c\u6709\u5c5e\u6027(property)\u3002\u6240\u4ee5bug\u7f16\u53f7\u3001\u5f00\u53d1\u4eba\u5458\u7684\u540d\u5b57\u548c\u5ba1\u67e5\u65e5\u671f\u5c06\u662fDeBugInfo\u7c7b\u5fc5\u987b\u7684\u5b9a\u4f4d(positional)\u53c2\u6570\uff0c\u6d88\u606f\u5c06\u662f\u4e00\u4e2a\u53ef\u9009\u7684\u547d\u540d(named)\u53c2\u6570\u3002\r\n             * \u6bcf\u4e2a\u7279\u6027\u5fc5\u987b\u81f3\u5c11\u6709\u4e00\u4e2a\u6784\u9020\u51fd\u6570\u3002\u5fc5\u9700\u7684\u5b9a\u4f4d\uff08positional\uff09\u53c2\u6570\u5e94\u901a\u8fc7\u6784\u9020\u51fd\u6570\u4f20\u9012\u3002\r\n             * \r\n             * \u89c1\u4e0bDeBugInfo\u7c7b\r\n             * \r\n             * \r\n             * \u5e94\u7528\u81ea\u5b9a\u4e49\u7279\u6027\r\n             * \u901a\u8fc7\u628a\u7279\u6027\u653e\u7f6e\u5728\u7d27\u63a5\u7740\u5b83\u7684\u76ee\u6807\u4e4b\u524d\uff0c\u6765\u5e94\u7528\u7279\u6027\r\n             * \r\n             * \u89c1\u4e0bRectangle\u7c7b\r\n             *\/\r\n\r\n            \/\/\u53cd\u5c04\r\n            \/*\r\n             * \u53cd\u5c04\u6307\u7a0b\u5e8f\u53ef\u4ee5\u8bbf\u95ee\u3001\u68c0\u6d4b\u548c\u4fee\u6539\u5b83\u672c\u8eab\u72b6\u6001\u6216\u884c\u4e3a\u7684\u4e00\u79cd\u80fd\u529b\r\n             * \u7a0b\u5e8f\u96c6\u5305\u542b\u6a21\u5757\uff0c\u800c\u6a21\u5757\u5305\u542b\u7c7b\u578b\uff0c\u7c7b\u578b\u53c8\u5305\u542b\u6210\u5458\u3002\u53cd\u5c04\u5219\u63d0\u4f9b\u4e86\u5c01\u88c5\u7a0b\u5e8f\u96c6\u3001\u6a21\u5757\u548c\u7c7b\u578b\u7684\u5bf9\u8c61\u3002\r\n             * \u4f60\u53ef\u4ee5\u4f7f\u7528\u53cd\u5c04\u52a8\u6001\u7684\u521b\u5efa\u7c7b\u578b\u7684\u5b9e\u4f8b\uff0c\u5c06\u7c7b\u578b\u7ed1\u5b9a\u5230\u73b0\u6709\u5bf9\u8c61\uff0c\u6216\u4ece\u73b0\u6709\u5bf9\u8c61\u83b7\u53d6\u7c7b\u578b\u3002\u7136\u540e\uff0c\u8c03\u7528\u7c7b\u578b\u7684\u65b9\u6cd5\u6216\u8bbf\u95ee\u5176\u5b57\u6bb5\u548c\u5c5e\u6027\u3002\r\n             * \r\n             * \u4f18\u70b9\uff1a\r\n             * 1.\u53cd\u5c04\u63d0\u9ad8\u4e86\u7a0b\u5e8f\u7684\u7075\u6d3b\u6027\u548c\u6269\u5c55\u6027\r\n             * 2.\u964d\u4f4e\u8026\u5408\u6027\uff0c\u63d0\u9ad8\u81ea\u9002\u5e94\u80fd\u529b\r\n             * 3.\u5b83\u5141\u8bb8\u7a0b\u5e8f\u521b\u5efa\u548c\u63a7\u5236\u4efb\u4f55\u7c7b\u7684\u5bf9\u8c61\uff0c\u65e0\u9700\u63d0\u524d\u786c\u7f16\u7801\u76ee\u6807\u7c7b\r\n             * \u7f3a\u70b9\uff1a\r\n             * 1.\u6027\u80fd\u95ee\u9898\uff1a\u4f7f\u7528\u53cd\u5c04\u57fa\u672c\u4e0a\u662f\u4e00\u79cd\u89e3\u91ca\u64cd\u4f5c\uff0c\u7528\u4e8e\u5b57\u6bb5\u548c\u65b9\u6cd5\u63a5\u5165\u65f6\u8981\u8fdc\u6162\u4e8e\u76f4\u63a5\u4ee3\u7801\u3002\u56e0\u6b64\u53cd\u5c04\u673a\u5236\u4e3b\u8981\u5e94\u7528\u5728\u5bf9\u7075\u6d3b\u6027\u548c\u6269\u5c55\u6027\u8981\u6c42\u5f88\u9ad8\u7684\u7cfb\u7edf\u6846\u67b6\u4e0a\uff0c\u666e\u901a\u7a0b\u5e8f\u4e0d\u5efa\u8bae\u4f7f\u7528\u3002\r\n             * 2.\u4f7f\u7528\u53cd\u5c04\u4f1a\u6a21\u7cca\u7a0b\u5e8f\u5185\u90e8\u7684\u903b\u8f91\uff1b\u7a0b\u5e8f\u5458\u5e0c\u671b\u5728\u6e90\u4ee3\u7801\u4e2d\u770b\u5230\u7a0b\u5e8f\u7684\u903b\u8f91\uff0c\u53cd\u5c04\u5374\u7ed5\u8fc7\u4e86\u6e90\u4ee3\u7801\u7684\u6280\u672f\uff0c\u56e0\u6b64\u4f1a\u5e26\u6765\u7ef4\u62a4\u95ee\u9898\uff0c\u53cd\u5c04\u4ee3\u7801\u6bd4\u76f8\u5e94\u7684\u76f4\u63a5\u4ee3\u7801\u66f4\u590d\u6742\u3002\r\n             * \r\n             * \r\n             * 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    * System.Reflection.MemberInfo info = typeof(MyClass);\r\n             * \r\n             *\/\r\n            System.Reflection.MemberInfo info = typeof(MyClass2);\r\n            object&#91;] attributes = info.GetCustomAttributes(true);\r\n            for(int i = 0;i&lt;attributes.Length;i++)\r\n            {\r\n                Console.WriteLine(attributes&#91;i]);\r\n            }\r\n\r\n            \/\/\u83b7\u53d6Rectangle\u4e0a\u7684DeBugInfo\u4fe1\u606f\r\n            Rectangle r = new Rectangle(4.5, 7.5);\r\n            r.Display();\r\n            Type type = typeof(Rectangle);\r\n            \/\/\u904d\u5386Rectangle\u7c7b\u7684\u7279\u6027\r\n            foreach(Object attributes2 in type.GetCustomAttributes(false))\r\n            {\r\n                DeBugInfo dbi = (DeBugInfo)attributes2;\r\n                if(null != dbi)\r\n                {\r\n                    Console.WriteLine(\"Bug no: {0}\", dbi.BugNo);\r\n                    Console.WriteLine(\"Developer: {0}\", dbi.Developer);\r\n                    Console.WriteLine(\"Last Reviewed: {0}\", dbi.LastReview);\r\n                    Console.WriteLine(\"Remarks: {0}\", dbi.Message);\r\n                }\r\n            }\r\n            \/\/\u904d\u5386\u65b9\u6cd5\u7279\u6027\r\n            foreach(MethodInfo mi in type.GetMethods())\r\n            {\r\n                foreach(Attribute ai in mi.GetCustomAttributes(true))\r\n                    {\r\n                    DeBugInfo dbi = (DeBugInfo)ai;\r\n                    if (null != dbi)\r\n                    {\r\n                        Console.WriteLine(\"Bug no: {0}\", dbi.BugNo);\r\n                        Console.WriteLine(\"Developer: {0}\", dbi.Developer);\r\n                        Console.WriteLine(\"Last Reviewed: {0}\", dbi.LastReview);\r\n                        Console.WriteLine(\"Remarks: {0}\", dbi.Message);\r\n                    }\r\n                }\r\n            }\r\n            Console.ReadKey();\r\n         }\r\n\r\n        &#91;Obsolete(\"Don't use OldMethod, use NewMethod instead\", true)]\r\n        static void OldMethod()\r\n        {\r\n            Console.WriteLine(\"It is the old method.\");\r\n        }\r\n\r\n        static void NewMethod()\r\n        {\r\n            Console.WriteLine(\"It is the new method.\");\r\n        }\r\n\r\n        static void func1()\r\n        {\r\n            MyClass.Message(\"in func1.\");\r\n            func2();\r\n        }\r\n\r\n        static void func2()\r\n        {\r\n            MyClass.Message(\"in func2.\");\r\n        }\r\n    }\r\n\r\n    &#91;AttributeUsage(AttributeTargets.All)]\r\n    public class HelpAttribute: System.Attribute\r\n    {\r\n        public readonly string Url;\r\n        public string Topic\/\/Topic\u662f\u4e00\u4e2a\u547d\u540d(named)\u53c2\u6570\r\n        {\r\n            get\r\n            {\r\n                return topic;\r\n            }\r\n            set\r\n            {\r\n                topic = value;\r\n            }\r\n        }\r\n        public HelpAttribute(string url) \/\/url\u662f\u4e00\u4e2a\u5b9a\u4f4d(positional)\u53c2\u6570\r\n        {\r\n            this.Url = url;\r\n        }\r\n        private string topic;\r\n    }\r\n\r\n    &#91;HelpAttribute(\"Information on the class MyClass2\")]\r\n    class MyClass2\r\n    {\r\n\r\n    }\r\n\r\n    &#91;DeBugInfo(45, \"Zara Ali\", \"12\/8\/2012\", Message = \"Return type mismatch\")]\r\n    &#91;DeBugInfo(49, \"Nuha Ali\", \"10\/10\/2012\", Message = \"Unused variable\")]\r\n    class Rectangle\r\n    {\r\n        \/\/\u6210\u5458\u53d8\u91cf\r\n        protected double length;\r\n        protected double width;\r\n        public Rectangle(double l, double w)\r\n        {\r\n            length = l;\r\n            width = w;\r\n        }\r\n\r\n        &#91;DeBugInfo(55, \"Zara Ali\", \"19\/10\/2012\", Message =\"Return type mismatch\")]\r\n        public double GetArea()\r\n        {\r\n            return length * width;\r\n        }\r\n\r\n        &#91;DeBugInfo(56, \"Zara Ali\", \"19\/10\/2012\")]\r\n        public void Display()\r\n        {\r\n            Console.WriteLine(\"Length: {0}\", length);\r\n            Console.WriteLine(\"Width: {0}\", width);\r\n            Console.WriteLine(\"Area: {0}\", GetArea());\r\n        }\r\n\r\n    }\r\n\r\n    \/\/\u4e00\u4e2a\u81ea\u5b9a\u4e49\u7279\u6027BugFix\u88ab\u8d4b\u7ed9\u7c7b\u53ca\u5176\u6210\u5458\r\n    &#91;AttributeUsage(AttributeTargets.Class |\r\n        AttributeTargets.Constructor |\r\n        AttributeTargets.Field |\r\n        AttributeTargets.Method |\r\n        AttributeTargets.Property,\r\n        AllowMultiple = true)]\r\n    public class DeBugInfo : System.Attribute\r\n    {\r\n        private int bugNo;\r\n        private string developer;\r\n        private string lastReview;\r\n        private string message;\r\n\r\n        public DeBugInfo(int b, string dev, string d)\r\n        {\r\n            this.bugNo = b;\r\n            this.developer = dev;\r\n            this.lastReview = d;\r\n        }\r\n\r\n        public int BugNo\r\n        {\r\n            get\r\n            {\r\n                return bugNo;\r\n            }\r\n        }\r\n        public string Developer\r\n        {\r\n            get\r\n            {\r\n                return developer;\r\n            }\r\n        }\r\n        public string LastReview\r\n        {\r\n            get\r\n            {\r\n                return lastReview;\r\n            }\r\n        }\r\n        public string Message\r\n        {\r\n            get\r\n            {\r\n                return message;\r\n            }\r\n            set\r\n            {\r\n                message = value;\r\n            }\r\n        }\r\n    }\r\n\r\n    public class MyClass\r\n    {\r\n        \/\/message only show on DEBUG_MODE\r\n        &#91;Conditional(\"DEBUG_MODE\")]\r\n        public static void Message(string msg)\r\n        {\r\n            Console.WriteLine(msg);\r\n        }\r\n    }\r\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[19],"tags":[],"_links":{"self":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/278"}],"collection":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=278"}],"version-history":[{"count":2,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/278\/revisions"}],"predecessor-version":[{"id":282,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=\/wp\/v2\/posts\/278\/revisions\/282"}],"wp:attachment":[{"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=278"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=278"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fengjijiao.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=278"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}