如何通过反射调用一些没有任何参数和任何返回值的方法？

Question

How to call some method via Reflection without any parameters and any return values?

Here is MSDN sample

// Define a class with a generic method.
public class Example
{
    public static void Generic<T>()
    {
        Console.WriteLine("\r\nHere it is: {0}", "DONE");
    }
}

What should be within typeof(???) then?

MethodInfo miConstructed = mi.MakeGenericMethod(typeof(???));

Thank you!!!

Answer 1

Before being able to invoke a generic method you need to specify its generic argument(s). So you pass the type you want to be used as generic argument:

public class Example
{
    public static void Generic<T>()
    {
        Console.WriteLine("The type of T is: {0}", typeof(T));
    }
}

class Program
{
    static void Main()
    {
        var mi = typeof(Example).GetMethod("Generic");
        MethodInfo miConstructed = mi.MakeGenericMethod(typeof(string));
        miConstructed.Invoke(null, null);
    }
}

which should print:

The type of T is: System.String

Answer 2

If you were invoking that through C#, you would need to supply a type, for example:

Example.Generic<int>();

that requirement does not change; simply, that line would become:

mi.MakeGenericMethod(typeof(int)).Invoke(null, null);

For a complete, working illustration:

class Example
{
    public static void Generic<T>()
    {
        System.Console.WriteLine("\r\nHere it is: {0}", "DONE");
    }
    static void Main()
    {
        var mi = typeof (Example).GetMethod("Generic");
        mi.MakeGenericMethod(typeof(int)).Invoke(null, null);
    }
}