How to distinguish MethodBase in generics

问题

I have a cache based on

Dictionary<MethodBase, string>

The key is rendered from MethodBase.GetCurrentMethod. Everything worked fine until methods were explicitly declared. But one day it is appeared that:

Method1<T>(string value)

Makes same entry in Dictionary when T gets absolutely different types.

So my question is about better way to cache value for generic methods. (Of course I can provide wrapper that provides GetCache and equality encountered generic types, but this way doesn't look elegant).

Update Here what I exactly want:

static Dictionary<MethodBase, string> cache = new Dictionary<MethodBase, string>();
static void Method1<T>(T g) 
{
    MethodBase m1 = MethodBase.GetCurrentMethod();
    cache[m1] = "m1:" + typeof(T);
}
public static void Main(string[] args)
{
    Method1("qwe");
    Method1<Stream>(null);
    Console.WriteLine("===Here MUST be exactly 2 entry, but only 1 appears==");
    foreach(KeyValuePair<MethodBase, string> kv in cache)
        Console.WriteLine("{0}--{1}", kv.Key, kv.Value);
}

回答1:

Use MakeGenericMethod, if you can:

using System;
using System.Collections.Generic;
using System.Reflection;

class Program
{
    static Dictionary<MethodBase, string> cache = new Dictionary<MethodBase, string>();

    static void Main()
    {
        Method1(default(int));
        Method1(default(string));
        Console.ReadLine();
    }

    static void Method1<T>(T g)
    {
        var m1 = (MethodInfo)MethodBase.GetCurrentMethod();
        var genericM1 = m1.MakeGenericMethod(typeof(T)); // <-- This distinguishes the generic types
        cache[genericM1] = "m1:" + typeof(T);
    }
}

回答2:

This is not possible; a generic method has a single MethodBase; it doesn't have one MethodBase per set of generic arguments.

来源：https://stackoverflow.com/questions/1940436/how-to-distinguish-methodbase-in-generics

标签

.net

generics

hashcode

equality

methodbase