C#/.NET Generics和Cdecl Varargs Bug？

Question

为什么Foo()成功但却Bar()抛出了BadImageFormatException？

using System.Runtime.InteropServices;
using System.Text;

static class Program
{
    [DllImport("msvcrt.dll", CallingConvention = CallingConvention.Cdecl)]
    static extern int sprintf([Out] StringBuilder buf, string format, __arglist);

    static void Main(string[] args)
    {
        Foo<int>(2); //Runs fine
        Bar<int>(2); //Error: "The signature is incorrect"
    }

 static void Foo<T>(int a) { sprintf(new StringBuilder(8), "%d", __arglist(a)); }
 static void Bar<T>(T   a) { sprintf(new StringBuilder(8), "%d", __arglist(a)); }
}

Answer 1

尝试这样：

using System;
using System.Runtime.InteropServices;
using System.Text;

static class Program
{
    [DllImport("msvcrt.dll", CallingConvention = CallingConvention.Cdecl)]
    static extern int sprintf([Out] StringBuilder buf, string format, params object[] args);

    static void Main(string[] args)
    {
        Foo(2);
        Bar<int>(2);
    }

    static void Foo(int a) { sprintf(new StringBuilder(8), "%d", a); }
    static void Bar<T>(T a){ sprintf(new StringBuilder(8), "%d", a); }
}