使用Assembly.LoadFrom加载通用类型 [英] Loading a generic type using Assembly.LoadFrom

问题描述

在提到乔恩斯基特这里的答案：通实例化的System.Type作为一个类型参数的泛型类

Referring to the answer by Jon Skeet here: Pass An Instantiated System.Type as a Type Parameter for a Generic Class

我需要加载基于一般类型的名称的通用型，这是为通用类型参数的类型的名称。因此，从乔恩的例子，我将有：

I need to load a Generic type based on the name of the generic type, and the name of the type that is the type parameter for the generic. So from Jon's example I would have:

string genName = "MyNamespace.Generic";
string itemName = "System.String";

我有以下的代码，将基于类型的名称和一个完全合理的负载类型集名称/路径。它工作正常的简单类型

I have the following code that will load a type based on the name of the type and a fully justified assembly name/path. It works fine for "simple types"

public Type GetTypeOf(string assemblyPath, string className)
{
    var asmbly = System.Reflection.Assembly.LoadFrom(assemblyPath); //open assembly
    return asmbly.GetType(className, true, true); //throws error, not case sensitive
}

我希望利用这个如下

I was hoping to use this as follows:

//Get the types
var genTyp = GetTypeOf(genPath,genName);
var itemTyp = GetTypeOf(itemPath,itemName);

//Put them together:
var typ = getType.MakeGenericType(itemTyp);

这翻倒在了第一行 System.TypeLoadException 说明：

This falls over on the first line with a System.TypeLoadException stating:

Could not load type <TypeName here> from assembly <AssemblyName here>

我已经尝试了一些创建通用的排列，包括提供完整的类名称 MyNamespace.Generic<&System.String GT; 。它正常工作时，我指定一个非泛型类型从包含泛型类型相同的程序集加载。

I've tried a number of permutations of creating the generic, included supplying the full class name MyNamespace.Generic<System.String>. It works correctly when I specify a non-generic type to load from the same assembly that contains the generic type.

推荐答案

不幸的是，使用的GetType与泛型类型是不是可读。您必须使用完全限定的类型名称，即使是一般的参数：。例如， TestType<对象> 读这样的：

Unfortunately, using GetType with generic types is not that readable. You have to use the full qualified type name, even for the generic parameters:. For example, TestType<object> reads like this:

TestType`1[[System.Object, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]]

您的示例代码不包括类型声明，所以你要玩这个。你可以试试这个代码段，看看有什么调试器说：

Your sample code does not include the type declarations, so you have to play around with this. You can try this code snippet and take a look what the debugger says:

string typeName = typeof(MyNamespace.Generic<>).Name;
string fullTypeName = typeof(MyNamespace.Generic<>).FullName;

结果应该可以帮助您得到正确的类型名称。

The results should help you getting the correct type name.

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