如何通过超时实现WNetAddConnection2的等效?

时间:2012-02-17 04:44:01

标签: c# windows winapi networking

以下对WNetAddConnection2的调用似乎永远挂起。请注意,机器名称是故意错误的 - 我希望快速失败而不是永久阻止。有没有办法实现类似的功能,但有超时?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Diagnostics;

namespace WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        [StructLayout(LayoutKind.Sequential)]
        public class NETRESOURCE
        {
            public int dwScope;
            public int dwType;
            public int dwDisplayType;
            public int dwUsage;
            public string LocalName;
            public string RemoteName;
            public string Comment;
            public string Provider;
        }
        [DllImport("mpr.dll")]
        public static extern int WNetAddConnection2(NETRESOURCE netResource, string password, string username, int flags);

        private void Form1_Load(object sender, EventArgs e)
        {
            NETRESOURCE myResource = new NETRESOURCE();
            myResource.dwScope = 0;
            myResource.dwType = 0; //RESOURCETYPE_ANY
            myResource.dwDisplayType = 0;
            myResource.LocalName = "";
            myResource.RemoteName = @"\\invalid.machine.com";
            myResource.dwUsage = 0;
            myResource.Comment = "";
            myResource.Provider = "";

            int returnValue = WNetAddConnection2(myResource, "password", "username", 0); //hangs forever
            Debug.Print("Finished connecting");
        }
    }
}

1 个答案:

答案 0 :(得分:1)

在早期版本的Windows上,无法终止卡在其中一个WNetAddConnection函数中的进程。这已在Vista中修复。 According to Larry Osterman,修复程序是CancelSynchronousIo函数。

您的问题的解决方案是:

  1. 启动新线程以运行WNetAddConnection2
  2. 设置计时器或等待现有主题。
  3. 超时后调用CancelSynchronousIo指定连接线程的句柄。
  4. 我想不出为什么这会与.Net发生严重互动的原因,但我还没有尝试过......