C# 从C调用WSASend#

这是我的代码，但我没有成功：

Unmanaged.WsaBuf buffer =
    Unmanaged.WsaBuf.Create("Blah Blah");

IntPtr bufferPointer = Marshal.AllocHGlobal(Marshal.SizeOf(buffer));
Marshal.StructureToPtr(buffer, bufferPointer, true);

IntPtr o;
SocketError error = Unmanaged.WSA_Send(
    socket,
    bufferPointer,
    1,
    out o,
    SocketFlags.None,
    IntPtr.Zero,
    IntPtr.Zero);

下面是方法声明：

    [DllImport("Ws2_32.dll", SetLastError = true, EntryPoint = "WSASend")]
    public static extern SocketError WSA_Send(IntPtr socket, IntPtr buffer, int len, out IntPtr numberOfBytesSent, SocketFlags flags, IntPtr overlapped, IntPtr completionRoutine);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct WsaBuf
{
    public ulong Len;

    public IntPtr Buf;

    public static WsaBuf Create(string str)
    {
        byte[] connectBuf = Encoding.ASCII.GetBytes(str);
        GCHandle pinnedArray = GCHandle.Alloc(connectBuf, GCHandleType.Pinned);
        return new WsaBuf { Buf = pinnedArray.AddrOfPinnedObject(), Len = (ulong)connectBuf.Length };
    }

    public void Free()
    {
        if (!Buf.Equals(IntPtr.Zero))
        {
            GCHandle.FromIntPtr(Buf).Free();
        }
    }
}

这是我的WSABUF宣言：

    [DllImport("Ws2_32.dll", SetLastError = true, EntryPoint = "WSASend")]
    public static extern SocketError WSA_Send(IntPtr socket, IntPtr buffer, int len, out IntPtr numberOfBytesSent, SocketFlags flags, IntPtr overlapped, IntPtr completionRoutine);

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct WsaBuf
{
    public ulong Len;

    public IntPtr Buf;

    public static WsaBuf Create(string str)
    {
        byte[] connectBuf = Encoding.ASCII.GetBytes(str);
        GCHandle pinnedArray = GCHandle.Alloc(connectBuf, GCHandleType.Pinned);
        return new WsaBuf { Buf = pinnedArray.AddrOfPinnedObject(), Len = (ulong)connectBuf.Length };
    }

    public void Free()
    {
        if (!Buf.Equals(IntPtr.Zero))
        {
            GCHandle.FromIntPtr(Buf).Free();
        }
    }
}

---

我在另一边什么也没收到。有什么想法吗？

u_long

是

unsigned long

，它映射到

uint

，因为它在Microsoft Visual C编译器上是一个4字节的量

Len

应该是

uint

。可能，

WSASend

只查看了前4个字节，发现它们是

0

，这是一个零长度的缓冲区

---

顺便说一句，您误用了

GCHandle.FromIntPtr

。看看这些文档，看看它到底有什么作用。这个问题无关紧要，所以我不会详细说明。

当.NET公开TcpClient，甚至是

Socket

类时，为什么要使用WinSock？@johnsaunds这是一个挂钩的情况，但MSDN很有用，还需要解决其他问题，但这似乎是解决发送问题的方法。