为什么C在编程中如此重要？

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它可以使用如下方式实现：

csharpFieldInfo field=fieldof(string.Empty);MethodInfo method1=methodof(int.ToString);MethodInfo method2=methodof(int.ToString(IFormatProvider));fieldof可编译为IL指令，例如：ldtoken fieldcallvirt FieldInfo.Get

它们可以如下使用：

FieldInfo field = fieldof(string.Empty); MethodInfo method1 = methodof(int.ToString); MethodInfo method2 = methodof(int.ToString(IFormatProvider));

fieldof可以编译为IL,如下：

ldtoken <field> call FieldInfo.GetFieldFromHandle

methodof可以编译为IL为：

ldtoken <method> call MethodBase.GetMethodFromHandle

每当使用typeof运算符时,您都可以获得完美的查找所有引用结果.不幸的是,一旦你去了田野或方法,你最终会遇到令人讨厌的黑客攻击.我想你可以做以下事情……或者你可以回去按名字命名.

public static FieldInfo fieldof<T>(Expression<Func<T>> expression) { MemberExpression body = (MemberExpression)expression.Body; return (FieldInfo)body.Member; } public static MethodInfo methodof<T>(Expression<Func<T>> expression) { MethodCallExpression body = (MethodCallExpression)expression.Body; return body.Method; } public static MethodInfo methodof(Expression<Action> expression) { MethodCallExpression body = (MethodCallExpression)expression.Body; return body.Method; } public static void Test() { FieldInfo field = fieldof(() => string.Empty); MethodInfo method1 = methodof(() => default(string).ToString()); MethodInfo method2 = methodof(() => default(string).ToString(default(IFormatProvider))); MethodInfo method3 = methodof(() => default(List<int>).Add(default(int))); } Eric Lippert(关于C#设计团队)对此主题有一个很好的概述/讨论 here.引用：

It’s an awesome feature that pretty much everyone involved in the design process wishes we could do, but there are good practical reasons why we choose not to. If there comes a day when designing it and implementing it is the best way we could spend our limited budget, we’ll do it. Until then, use Reflection.