c# - 如何使用反射调用泛型方法？(How do I use reflection to call a generic method?)

Question

What's the best way to call a generic method when the type parameter isn't known at compile time, but instead is obtained dynamically at runtime?

(当类型参数在编译时未知，而是在运行时动态获取时，调用通用方法的最佳方法是什么？)

Consider the following sample code - inside the Example() method, what's the most concise way to invoke GenericMethod<T>() using the Type stored in the myType variable?

(考虑以下示例代码-在Example()方法内部，使用存储在myType变量中的Type调用GenericMethod<T>()的最简洁方法是什么？)

public class Sample
{
    public void Example(string typeName)
    {
        Type myType = FindType(typeName);

        // What goes here to call GenericMethod<T>()?
        GenericMethod<myType>(); // This doesn't work

        // What changes to call StaticMethod<T>()?
        Sample.StaticMethod<myType>(); // This also doesn't work
    }

    public void GenericMethod<T>()
    {
        // ...
    }

    public static void StaticMethod<T>()
    {
        //...
    }
}

  ask by Bevan translate from so

Answer 1

You need to use reflection to get the method to start with, then "construct" it by supplying type arguments with MakeGenericMethod :

(您需要使用反射来使方法开始，然后通过为MakeGenericMethod提供类型参数来“构造”它：)

MethodInfo method = typeof(Sample).GetMethod("GenericMethod");
MethodInfo generic = method.MakeGenericMethod(myType);
generic.Invoke(this, null);

For a static method, pass null as the first argument to Invoke .

(对于静态方法，将null作为第一个参数传递给Invoke 。)

That's nothing to do with generic methods - it's just normal reflection.

(这与泛型方法无关，只是正常的反映。)

As noted, a lot of this is simpler as of C# 4 using dynamic - if you can use type inference, of course.

(如前所述，从C＃4开始，使用dynamic很多事情都比较简单-当然，如果可以使用类型推断。)

It doesn't help in cases where type inference isn't available, such as the exact example in the question.

(在类型推断不可用的情况下（例如问题中的确切示例），它无济于事。)