如何将对象转换为Type类描述的类型？ [英] How to cast object to type described by Type class?

问题描述

我有一个对象：

  ExampleClass ex = new ExampleClass（）; 
  

和：

 类型TargetType 
  

我想将ex转换为TargetType描述的类型，如下所示：

 对象o =（TargetType）ex; 
  

但是当我这样做时，我得到：

< blockquote>

类型或命名空间名称't'可能找不到

去做这个？

我想获得类似这样的东西：

p>

  public CustomClass MyClassOuter 
 {
 get 
 {
 return（CustomClass）otherClass; 
} 
} 
 
 private otherClass; 
  

因为我会有很多这样的属性，我想这样做：

  public CustomClass MyClassOuter 
 {
 get 
 {
 return（GetThisPropertyType（））otherClass; 
} 
} 
 
 private SomeOtherTypeClass otherClass; 
  

上下文：

在我的类中，我需要创建许多属性。并在每一个替换铸造的类型的属性。它似乎对我没有意义（在我的上下文），因为我知道什么返回类型是，我想写一些类型的代码，将为我的铸造。也许是泛型的情况，我还不知道。

这就像我可以确保在这个属性，我得到正确的对象和正确的类型，我100％能够将其投射到属性类型。

所有我需要这样做，所以我不需要在每个属性中指定它必须转换值到CustomClass，我想做一些事

例如：

  class MYBaseClass 
 {
 protected List< Object> MyInternalObjects; 
} 
 
 class MyClass 
 {
 public SpecialClass MyVeryOwnSpecialObject 
 {
 get 
 {
 return（SpecialClass） MyInteralObjects [MyVeryOwnSpecialObject]; 
} 
} 
} 
  

很多属性像这样一个上面 - 但有2个问题：

1）我需要在MyInternalObjects指定对象的名称，但它是相同的属性名称。这个我解决了System.Reflection.MethodBase.GetCurrentMethod（）。名称。

2）在每个属性，我需要将对象从MyInternalObjects转换为不同的类型。在MyVeryOwnSpecialObject中例如 - 到SpecialClass。

这就是为什么我想这样做：

  class MYBaseClass 
 {
 protected List< Object> MyInternalObjects; 
} 
 
 class MyClass 
 {
 public SpecialClass MyVeryOwnSpecialObject 
 {
 get 
 {
 return（GetPropertyType ））MyInteralObjects [System.Reflection.MethodBase.GetCurrentMethod（）。Name]; 
} 
} 
} 
  

做什么的？因为在我的应用程序中，我将有安全类型等所有好处（intellisense）。

第二个：但现在你会失去类型安全在这个地方吗？

解决方案

现在看起来是不可能的，但是很快就会提供.NET 4.0中称为动态的新功能：

http://www.codeguru.com/vb/vbnet30/article.php/c15645__4/

I have a object:

ExampleClass ex = new ExampleClass();

And:

Type TargetType

I would like to cast ex to type described by TargetType like this:

Object o = (TargetType) ex;

But when I do this I get:

The type or namespace name 't' could not be found

So how to do this? Am I missing something obious here?

Update:

I would like to obtain something like this:

public CustomClass MyClassOuter
{
   get
   {
        return (CustomClass) otherClass;
   }
}

private otherClass;

And because I will have many properties like this I would like do this:

public CustomClass MyClassOuter
{
   get
   {
        return (GetThisPropertyType()) otherClass;
   }
}

private SomeOtherTypeClass otherClass;

Context:

Normally in my context in my class I need to create many properties. And in every one replace casting to the type of property. It does not seem to have sense to me (in my context) because I know what return type is and I would like to write some kind of code that will do the casting for me. Maybe it's case of generics, I don't know yet.

It's like I can assure in this property that I get the right object and in right type and am 100% able to cast it to the property type.

All I need to do this so that I do not need to specify in every one property that it has to "cast value to CustomClass", I would like to do something like "cast value to the same class as this property is".

For example:

class MYBaseClass
{
   protected List<Object> MyInternalObjects;
}

class MyClass
{
   public SpecialClass MyVeryOwnSpecialObject
   {
      get
      {
           return (SpecialClass) MyInteralObjects["MyVeryOwnSpecialObject"];
      }
   }
}

And ok - I can make many properties like this one above - but there is 2 problems:

1) I need to specify name of object on MyInternalObjects but it's the same like property name. This I solved with System.Reflection.MethodBase.GetCurrentMethod().Name.

2) In every property I need to cast object from MyInternalObjects to different types. In MyVeryOwnSpecialObject for example - to SpecialClass. It's always the same class as the property.

That's why I would like to do something like this:

class MYBaseClass
{
   protected List<Object> MyInternalObjects;
}

class MyClass
{
   public SpecialClass MyVeryOwnSpecialObject
   {
      get
      {
           return (GetPropertyType()) MyInteralObjects[System.Reflection.MethodBase.GetCurrentMethod().Name];
      }
   }
}

And now concerns: Ok, what for? Because further in my application I will have all benefits of safe types and so on (intellisense).

Second one: but now you will lost type safety in this place? No. Because I'm very sure that I have object of my type on a list.

解决方案

Now it seems to be impossible, but soon will be available with new feature in .NET 4.0 called "dynamic":

http://www.codeguru.com/vb/vbnet30/article.php/c15645__4/

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