private static OleDbConnection conn;
        public static OleDbConnection Conn
        {

            get
            {
                try
                {

                    string connstr = "";

                    if (conn == null)
                        conn = new OleDbConnection(connstr);
                    if (conn.State == ConnectionState.Closed)
                        conn.Open();
                    if (conn.State == ConnectionState.Broken)
                    {
                        conn.Close();
                        conn.Open();
                    }
                    return conn;

                }
                catch (Exception ex)
                {

                    throw;
                }
            }
        }


        //查询:DataTable
        public static DataTable GetTable(string SqlStr)
        {
            try
            {
                OleDbDataAdapter dap = new OleDbDataAdapter(SqlStr, Conn);
                DataSet ds = new DataSet();
                dap.Fill(ds);
                conn.Close();
                return ds.Tables[0];
            }
            catch (Exception ex)
            {

                throw;
            }
        }

------解决方案--------------------
看一下连接语句是否写错

------解决方案--------------------
上面的Xp，
win7如下
C# code

win7中Spy++才发现开始菜单就是窗口
 class Program
    {
        // 获得窗体句柄
        [DllImport("user32.dll")]
        public static extern IntPtr FindWindow(String className, String captionName);
        [DllImport("user32.dll")]
        public static extern bool ShowWindow(IntPtr hwnd, uint nCmdShow);
        static void Main(string[] args)
        {
            // 获得任务栏句柄
            var rwl = FindWindow("Shell_TrayWnd", null);
            //当nCmdShow=0：隐藏；=1：显示
            ShowWindow(rwl, 0);
            var rwl2 = FindWindow("Button", null);
            ShowWindow(rwl2, 0);
            Console.Read();
            ShowWindow(rwl2, 1);
            ShowWindow(rwl, 1);
        }
    }

------解决方案--------------------
我去，错了，回答错了地方

------解决方案--------------------
探讨


引用:
上面的Xp，
win7如下

C# code

win7中Spy++才发现开始菜单就是窗口
class Program
{
// 获得窗体句柄
[DllImport("user32.dll")]
public static extern IntPtr FindWindow(String className, String……
……