blocks|key|3777991|text|不能从函数返回匿名类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3777992|从MSDN+documentation|offset|length|3777993|3777994|若要将匿名类型或包含匿名类型的集合传递到方法边界之外，必须首先将该类型强制转换为object。但是，这会使匿名类型的强类型失效。如果必须存储查询结果或将它们传递到方法边界之外，请考虑使用普通的命名结构或类，而不是匿名类型。|blockquote|3777995|3777996|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/bb397696.aspx^0|0|1|I|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@$D|U|E|V|1|W]]|A|$]]|$1|F|3|-4|5|6|7|X|8|@]|9|@]|A|$]]|$1|G|3|H|5|I|7|Y|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

You can't return an anonymous type from a function.

From the <a href="http://msdn.microsoft.com/en-us/library/bb397696.aspx" rel="nofollow noreferrer">MSDN documentation</a>:

<blockquote>
 To pass an anonymous type, or a collection that contains anonymous types, outside a method boundary, you must first cast the type to object. However, this defeats the strong typing of the anonymous type. If you must store your query results or pass them outside the method boundary, consider using an ordinary named struct or class instead of an anonymous type.
</blockquote>

blocks|key|3778015|text|匿名类型只是一个编译器生成的类，编译器不愿意告诉您类本身的名称。因此，除了返回对object的引用之外，没有其他方法可以从函数返回该类的实例。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3778016|entityMap^0|14|6|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

Anonymous type is just a compiler-generated class, and the compiler is not willing to tell you the name of the class itself. Therefore, there's no way you can return an instance of this class from a function other than returning a reference to an <code>object</code>.

blocks|key|4623083|text|好吧，我认为答案是:不要在声明的范围之外使用匿名类型。在这种情况下，创建一个简单类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4623084|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Well, I think the answer is: Don't use an anonymous type outside the scope where its declared. In this case create a simple type.

blocks|key|558024|text|正如其他答案所说，，你真的不应该这么做。但是，如果你坚持，那么有一个被称为“按示例转换”的令人讨厌的技巧可以让你做到这一点。here和here这两篇文章中提到了这项技术。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|558025|public+void+FuncB()
{
++++var+example+=+new+{+Id+=+0,+Name+=+string.Empty+};

++++var+obj+=+CastByExample(FuncA(),+example);
++++Console.WriteLine(obj.Name);
}

private+object+FuncA()
{
++++var+a+=+from+e+in+DB.Entities
++++++++++++where+e.Id+==+1
++++++++++++select+new+{+Id+=+e.Id,+Name+=+e.Name+};

++++return+a.FirstOrDefault();
}

private+T+CastByExample<T>(object+target,+T+example)
{
++++return+(T)target;
}|code-block|syntax|javascript|558026|(我不能为这次黑客攻击负责，尽管the+author+of+one+of+those+articles+says+that+he+doesn't+want+to+be+associated+with+it+either。他的名字可能很熟悉。)|558027|entityMap|0|LINK|mutability|MUTABLE|url|http://tomasp.net/blog/cannot-return-anonymous-type-from-method.aspx|1|http://msmvps.com/blogs/jon_skeet/archive/2009/01/09/horrible-grotty-hack-returning-an-anonymous-type-instance.aspx|2|https://webcache.googleusercontent.com/search?q=cache:x_rICZ2nnxUJ:https://blogs.msmvps.com/jonskeet/2009/01/09/horrible-grotty-hack-returning-an-anonymous-type-instance/%2B&cd=1&hl=en&ct=clnk&gl=us^0|1Q|4|0|1V|4|1|0|0|G|2L|2|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]|$A|10|B|11|1|12]]|C|$]]|$1|D|3|E|5|F|7|13|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|14|8|@]|9|@$A|15|B|16|1|17]]|C|$]]|$1|K|3|-4|5|6|7|18|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]|S|$5|N|O|P|C|$Q|T]]|U|$5|N|O|P|C|$Q|V]]]]

As the other answers have stated, you really shouldn't do this. But, if you insist, then there's a nasty hack known as "cast by example" which will allow you to do it. The technique is mentioned in a couple of articles, <a href="http://tomasp.net/blog/cannot-return-anonymous-type-from-method.aspx" rel="nofollow noreferrer">here</a> and <a href="http://msmvps.com/blogs/jon_skeet/archive/2009/01/09/horrible-grotty-hack-returning-an-anonymous-type-instance.aspx" rel="nofollow noreferrer">here</a>.

<pre><code>public void FuncB()
{
 var example = new { Id = 0, Name = string.Empty };

 var obj = CastByExample(FuncA(), example);
 Console.WriteLine(obj.Name);
}

private object FuncA()
{
 var a = from e in DB.Entities
 where e.Id == 1
 select new { Id = e.Id, Name = e.Name };

 return a.FirstOrDefault();
}

private T CastByExample&lt;T&gt;(object target, T example)
{
 return (T)target;
}
</code></pre>

(I can't take the credit for this hack, although <a href="https://webcache.googleusercontent.com/search?q=cache:x_rICZ2nnxUJ:https://blogs.msmvps.com/jonskeet/2009/01/09/horrible-grotty-hack-returning-an-anonymous-type-instance/+&amp;cd=1&amp;hl=en&amp;ct=clnk&amp;gl=us" rel="nofollow noreferrer">the author of one of those articles says that he doesn't want to be associated with it either</a>. His name might be familiar.)

blocks|key|1139489|text|将为本例创建一个类：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1139490|public+class+LISTFUNCA+++
{+++++++++++++++++++++++++
++++public+int+identificacion;++
++++public+string+nombre;++++++
}+++++|code-block|syntax|javascript|1139491|然后：|1139492|public+List<LISTFUNCA>+FuncA()+++
{++++++++++++++++++++++++++++++++++++++++++
++++var+lista+=+(from+e+in+DB.Entities+where+e.Id+==+1++++++++++++++++++++++++
++++++++++++++++select+new+{+identificacion+=+e.Id,+nombre+=+e.Name})
++++++++++++++++.FirstOrDefault();++
++++return+lista.ToList();+
}+++++|1139493|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

would create a class for this case: 

<pre><code>public class LISTFUNCA 
{ 
 public int identificacion; 
 public string nombre; 
} 
</code></pre>

then: 

<pre><code>public List&lt;LISTFUNCA&gt; FuncA() 
{ 
 var lista = (from e in DB.Entities where e.Id == 1 
 select new { identificacion = e.Id, nombre = e.Name})
 .FirstOrDefault(); 
 return lista.ToList(); 
} 
</code></pre>

blocks|key|1145531|text|如果你使用的是元组4.0，你可以使用.NET，你会返回一个Tuple<int,+string>。你可以为2.0/3.5实现你自己的元组，实际上其他人已经实现了，所以如果你愿意，你应该能够这样做。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1145532|entityMap^0|T|I|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

If you are using .NET 4.0, you can use Tuples for this, you'd return a <code>Tuple&lt;int, string&gt;</code>. You can implement your own Tuples for 2.0/3.5, and actually other people already have, so you should be able to do that if you like.

blocks|key|1139543|text|开源框架Impromptu-Interface将允许您将匿名对象强制转换为接口。它的优点是不那么繁琐，因为它将在程序集边界上按预期工作。它使用轻量级代理和dlr来实现这一点。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1139544|entityMap|0|LINK|mutability|MUTABLE|url|http://code.google.com/p/impromptu-interface/^0|4|J|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

The open source framework <a href="http://code.google.com/p/impromptu-interface/" rel="nofollow">Impromptu-Interface</a> will allow you to duck cast an anonymous object to an interface. It has the advantage of being less hacky because it will work as expected across assembly boundaries. It accomplishes this using a lightweight proxy and the dlr.

How do i access objects of an anonymous type outside the scope where its declared?

for e.g.

<pre><code>void FuncB()
{
var obj = FuncA();
Console.WriteLine(obj.Name);
}

??? FuncA()
{
var a = (from e in DB.Entities
where e.Id == 1
select new {Id = e.Id, Name = e.Name}).FirstOrDefault();

return a;
}
</code></pre>

Accessing C# Anonymous Type Objects

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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如何在声明匿名类型的作用域之外访问它的对象？例如void FuncB(){var obj = FuncA();Console.WriteLine(obj.Name);}??? FuncA(){var a = (from e in DB.Entitieswhere e.Id == 1select new {Id = e....

问访问C#匿名类型对象
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