blocks|key|2391380|text|在这种特殊情况下，它基本上是无法访问的。您正在创建一个lambda，它执行所讨论的方法。该lambda最终导致生成一个新方法，该方法最终成为Action委托的参数。这种方法与TargetHasOneTeam没有关系，只有当你深入研究正文中的IL指令时，它才是明显的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2391381|你可以跳过lambda，在这里做一个方法组转换。|2391382|TestThat(TargetHasOneTeam);|code-block|syntax|javascript|2391383|现在，TargetHasOneTeam被直接分配给委托实例，并且将在Delegate::MethodInfo属性中可见。|2391384|注意:一般来说，对于您遇到的问题来说，这不是一个好主意。方法的属性不应该影响它满足委托实例化的能力。如果可能的话，我会避免这种类型的检查。|2391385|entityMap^0|1Y|6|2F|G|0|0|0|3|G|Y|K|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|C]]|D|@]|E|$]]|$1|O|3|P|5|6|7|14|8|@]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|R|$]]

In this particular case it's essentially inaccessible. You are creating a lambda which executes the method in question. That lambda eventually results in a new method being generated which is eventually the argument of the <code>Action</code> delegate. That method has no relation to <code>TargetHasOneTeam</code> and is only apparently if you dig through the IL instructions in the body.

You could skip the lambda and do a method group conversion here. 

<pre><code>TestThat(TargetHasOneTeam);
</code></pre>

Now <code>TargetHasOneTeam</code> is being directly assigned to the delegate instance and would be visible in the <code>Delegate::MethodInfo</code> property. 

Note: In general though this is a bad idea for precisely the problem you're encountering. The attributes on the method shouldn't affect it's ability to satisfy the delegate instantiation. I would avoid this type of inspection if possible.

blocks|key|1375968|text|您可以使用Attribute.GetCustomAttribute获取任何成员的属性。首先检查是否定义了该属性。例如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1375969|public+static+void+TestThat(TestCaseBase.Action+action)
{
++++TestCaseResult+result+=+action.Invoke();
++++if(System.Attribute.IsDefined(action.Method,+typeof(TestDescriptionAttribute)))
++++{
++++++++var+attribute+=+(TestDescriptionAttribute)System.Attribute.GetCustomAttribute(action.Method,
++++++++++++typeof(TestDescriptionAttribute));
++++++++Console.WriteLine(attribute.TestDescription);
++++}
}|code-block|syntax|javascript|1375970|entityMap^0|5|S|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You can get the attribute of any member with <code>Attribute.GetCustomAttribute</code>. First check that the attribute is defined. For example:

<pre><code>public static void TestThat(TestCaseBase.Action action)
{
 TestCaseResult result = action.Invoke();
 if(System.Attribute.IsDefined(action.Method, typeof(TestDescriptionAttribute)))
 {
 var attribute = (TestDescriptionAttribute)System.Attribute.GetCustomAttribute(action.Method,
 typeof(TestDescriptionAttribute));
 Console.WriteLine(attribute.TestDescription);
 }
}
</code></pre>

blocks|key|2395896|text|如果将TestThat(()+=>+TargetHasOneTeam())+(将代理包装到另一个操作中)更改为TestThat(TargetHasOneTeam)，并按如下方式更改TestThat：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2395897|public+static+void+TestThat(TestCaseBase.Action+action)
{
++TestCaseResult+result+=+action.Invoke();
++var+attrs+=+action.GetInvocationList()[0].Method.GetCustomAttributes(true);

++//+I+want+to+get+the+value+of+the+TestDescription+attribute+here
}|code-block|syntax|javascript|2395898|会给你你想要的。|2395899|使用表达式：|2395900|public+static+void+TestThat(Expression<Func<TestResult>>+action)
{
++++var+attrs+=+((MethodCallExpression)action.Body).Method.GetCustomAttributes(true);

++++var+result+=+action.Compile()();
}|2395901|entityMap^0|3|Y|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|D|@]|E|$]]|$1|M|3|N|5|6|7|X|8|@]|D|@]|E|$]]|$1|O|3|P|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|Q|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|R|$]]

If you change <code>TestThat(() =&gt; TargetHasOneTeam())</code> (you wrapping your delegate into another action) to TestThat(TargetHasOneTeam) and change TestThat like this:

<pre><code>public static void TestThat(TestCaseBase.Action action)
{
 TestCaseResult result = action.Invoke();
 var attrs = action.GetInvocationList()[0].Method.GetCustomAttributes(true);

 // I want to get the value of the TestDescription attribute here
}
</code></pre>

will give you what you need.

With expressions:

<pre><code>public static void TestThat(Expression&lt;Func&lt;TestResult&gt;&gt; action)
{
 var attrs = ((MethodCallExpression)action.Body).Method.GetCustomAttributes(true);

 var result = action.Compile()();
}
</code></pre>

blocks|key|2395903|text|请参阅MSDN上的此示例。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2395904|class+TestAuthorAttribute
{
++static+void+Test()
++{
++++PrintAuthorInfo(typeof(FirstClass));
++++PrintAuthorInfo(typeof(SecondClass));
++++PrintAuthorInfo(typeof(ThirdClass));
++}

++private+static+void+PrintAuthorInfo(System.Type+t)
+{
++++System.Console.WriteLine("Author+information+for+{0}",+t);

++++//+Using+reflection.
++++System.Attribute[]+attrs+=+System.Attribute.GetCustomAttributes(t);++//+Reflection.

++++//+Displaying+output.
++++foreach+(System.Attribute+attr+in+attrs)
++++{
++++++++if+(attr+is+Author)
++++++++{
++++++++++++Author+a+=+(Author)attr;
++++++++++++System.Console.WriteLine("+++{0},+version+{1:f}",+a.GetName(),+a.version);
++++++++}
++++++}
++}|code-block|syntax|javascript|2395905|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/z919e8tw.aspx^0|3|4|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

See this example on <a href="http://msdn.microsoft.com/en-us/library/z919e8tw.aspx" rel="nofollow">MSDN</a>. 

<pre><code>class TestAuthorAttribute
{
 static void Test()
 {
 PrintAuthorInfo(typeof(FirstClass));
 PrintAuthorInfo(typeof(SecondClass));
 PrintAuthorInfo(typeof(ThirdClass));
 }

 private static void PrintAuthorInfo(System.Type t)
 {
 System.Console.WriteLine("Author information for {0}", t);

 // Using reflection.
 System.Attribute[] attrs = System.Attribute.GetCustomAttributes(t); // Reflection.

 // Displaying output.
 foreach (System.Attribute attr in attrs)
 {
 if (attr is Author)
 {
 Author a = (Author)attr;
 System.Console.WriteLine(" {0}, version {1:f}", a.GetName(), a.version);
 }
 }
 }
</code></pre>

I'm sure there's an answer already on the forum somewhere, but I haven't been able to find it so far. As per <a href="https://stackoverflow.com/questions/377217/c-sharp-delegate-for-two-methods-with-different-parameters">this example</a> I am using anonymous methods in conjunction with a delegate in order to have different methods with the different parameters but the same return type all work as function parameters:

<pre><code>public delegate TestCaseResult Action();
...

[TestDescription("Test whether the target computer has teaming configured")]
public TestCaseResult TargetHasOneTeam()
{
 // do some logic here and return
 // TestCaseResult
}

[TestDescription("Test whether the target computer has the named team configured")]
public TestCaseResult TargetHasNamedTeam(string teamName)
{
 // do some logic here and return
 // TestCaseResult
}
...

public static void TestThat(TestCaseBase.Action action)
{
 TestCaseResult result = action.Invoke();

 // I want to get the value of the TestDescription attribute here
}
...

// usage
TestThat(() =&gt; TargetHasOneTeam());

TestThat(() =&gt; TargetHasNamedTeam("Adapter5"));
</code></pre>

As you can see from the example, I'd really like to be able to get the TestDescriptionAttribute attribute from within the TestThat() function. I've already poked through the Action parameter which contains my method but haven't been able to "find" my TargetHasOneTeam() method.

Can I get a method attribute from a generic delegate?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我确信在论坛的某个地方已经有了答案，但到目前为止我还没有找到它。根据，我将匿名方法与委托结合使用，以便具有不同参数但返回类型相同的不同方法，所有方法都作为函数参数工作：public delegate TestCaseResult Action();...[TestDescription("Test whether th...

问我能从泛型委托中获取方法属性吗？
EN

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问我能从泛型委托中获取方法属性吗？EN