blocks|key|773520|text|不使用任何动态类型，让你的类实现一个接口，不是更好吗？然后，您可以在运行时检查对象是否实现了该接口，从而具有预期的方法(或属性)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|773521|public+interface+IMyInterface
{
+++void+Somemethod();
}


IMyInterface+x+=+anyObject+as+IMyInterface;
if(+x+!=+null+)
{
+++x.Somemethod();
}|code-block|syntax|javascript|773522|我认为这是唯一正确的方法。|773523|您所指的是鸭子类型，在您已经知道对象具有该方法，但编译器无法检查它的情况下，它很有用。例如，这在COM互操作方案中很有用。(查看this文章)|offset|length|773524|举个例子，如果你想把鸭子类型和反射结合起来，那么我认为你错过了鸭子类型的目标。|773525|entityMap|0|LINK|mutability|MUTABLE|url|http://www.devx.com/dotnet/Article/42590^0|0|0|0|1S|4|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|Z|8|@]|9|@$K|10|L|11|1|12]]|A|$]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

Wouldn't it be better to not use any dynamic types for this, and let your class implement an interface.
Then, you can check at runtime wether an object implements that interface, and thus, has the expected method (or property).

<pre><code>public interface IMyInterface
{
 void Somemethod();
}


IMyInterface x = anyObject as IMyInterface;
if( x != null )
{
 x.Somemethod();
}
</code></pre>

I think this is the only correct way.

The thing you're referring to is duck-typing, which is useful in scenarios where you already know that the object has the method, but the compiler cannot check for that.
This is useful in COM interop scenarios for instance. (check <a href="http://www.devx.com/dotnet/Article/42590">this</a> article)

If you want to combine duck-typing with reflection for instance, then I think you're missing the goal of duck-typing.

blocks|key|988819|text|通过反射|type|unstyled|depth|inlineStyleRanges|entityRanges|data|988820|+var+property+=+object.GetType().GetProperty("YourProperty")
+property.SetValue(object,some_value,null);|code-block|syntax|javascript|988821|类似的是for方法|988822|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

via Reflection

<pre><code> var property = object.GetType().GetProperty("YourProperty")
 property.SetValue(object,some_value,null);
</code></pre>

Similar is for methods

blocks|key|773573|text|你可以这样写：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|773574|public+static+bool+HasMethod(this+object+objectToCheck,+string+methodName)
{
++++var+type+=+objectToCheck.GetType();
++++return+type.GetMethod(methodName)+!=+null;
}+|code-block|syntax|javascript|773575|Edit+:你甚至可以做一个扩展方法，并像这样使用它|773576|myObject.HasMethod("SomeMethod");|773577|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|$]]

You could write something like that : 

<pre><code>public static bool HasMethod(this object objectToCheck, string methodName)
{
 var type = objectToCheck.GetType();
 return type.GetMethod(methodName) != null;
} 
</code></pre>

Edit : you can even do an extension method and use it like this

<pre><code>myObject.HasMethod("SomeMethod");
</code></pre>

blocks|key|988902|text|这是一个古老的问题，但我只是碰巧遇到了它。如果有多个方法具有该名称，则Type.GetMethod(string+name)将抛出AmbiguousMatchException，因此我们最好处理这种情况|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|988903|public+static+bool+HasMethod(this+object+objectToCheck,+string+methodName)
{
++++try
++++{
++++++++var+type+=+objectToCheck.GetType();
++++++++return+type.GetMethod(methodName)+!=+null;
++++}
++++catch(AmbiguousMatchException)
++++{
++++++++//+ambiguous+means+there+is+more+than+one+result,
++++++++//+which+means:+a+method+with+that+name+does+exist
++++++++return+true;
++++}
}+|code-block|syntax|javascript|988904|entityMap^0|Z|R|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|$]]

It is an old question, but I just ran into it.
<code>Type.GetMethod(string name)</code> will throw an AmbiguousMatchException if there is more than one method with that name, so we better handle that case

<pre><code>public static bool HasMethod(this object objectToCheck, string methodName)
{
 try
 {
 var type = objectToCheck.GetType();
 return type.GetMethod(methodName) != null;
 }
 catch(AmbiguousMatchException)
 {
 // ambiguous means there is more than one result,
 // which means: a method with that name does exist
 return true;
 }
} 
</code></pre>

blocks|key|988958|text|为了避免AmbiguousMatchException，我更愿意说|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|988959|objectToCheck.GetType().GetMethods().Count(m+=>+m.Name+==+method)+>+0|code-block|syntax|javascript|988960|entityMap^0|4|N|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|$]]

To avoid <code>AmbiguousMatchException</code>, I would rather say
<pre><code>objectToCheck.GetType().GetMethods().Count(m =&gt; m.Name == method) &gt; 0
</code></pre>

Using dynamic pattern perhaps? You can call any method/property using the dynamic keyword, right? How to check whether the method exist before calling myDynamicObject.DoStuff(), for example?

How to check whether an object has certain method/property?

编译器

也许使用动态模式？您可以使用dynamic关键字调用任何方法/属性，对吗？例如，在调用myDynamicObject.DoStuff()之前，如何检查该方法是否存在？

问如何检查对象是否有特定的方法/属性？
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