实现了界面可以像QQ一样像上伸缩

#region 类似QQ的往上伸缩的功能         /*         * 可以做一个像QQ一样往上收的功能         * 使用说明:         * 在窗体加载的事件中添加两句话         *  intOriHeight = this.Height;         *  JudgeWinMouPosition.Enabled = true;            */        //实现类似QQ可以伸缩到屏幕上方        #region 声明本程序中用到的API函数        //获取当前鼠标下可视化控件的函数        [System.Runtime.InteropServices.DllImport("user32.dll")]        public static extern int WindowFromPoint(int xPoint, int yPoint);        //获取指定句柄的父级函数        [System.Runtime.InteropServices.DllImport("user32.dll", ExactSpelling = true, CharSet = System.Runtime.InteropServices.CharSet.Auto)]        public static extern IntPtr GetParent(IntPtr hWnd);        //获取屏幕的大小        [System.Runtime.InteropServices.DllImport("user32.dll", EntryPoint = "GetSystemMetrics")]        private static extern int GetSystemMetrics(int mVal);        #endregion        #region 运行本程序需要声明的变量        private IntPtr CurrentHandle;//记录鼠标当前状态下控件的句柄        private int WindowFlag;//标记是否对窗体进行拉伸操作         private int intOriHeight;        #endregion        #region 获取鼠标当前状态下控件的句柄        /// <summary>        /// 获取鼠标当前状态下控件的句柄        /// </summary>        /// <param name="x">当前鼠标的X坐标</param>        /// <param name="y">当前鼠标的Y坐标</param>        /// <returns></returns>        public IntPtr MouseNowPosition(int x, int y)        {            IntPtr OriginalHandle;//声明保存原始句柄的变量            OriginalHandle = ((IntPtr)WindowFromPoint(x, y));//获取包含鼠标原始位置的窗口的句柄            CurrentHandle = OriginalHandle;//设置当前句柄            while (OriginalHandle != ((IntPtr)0))//循环判断鼠标是否移动            {                CurrentHandle = OriginalHandle;//记录当前的句柄                OriginalHandle = GetParent(CurrentHandle);//更新原始句柄            }            return CurrentHandle;  //返回当前的句柄        }        #endregion        public int OriHeight        {            get { return intOriHeight; }        }        private void JudgeWinMouPosition_Tick(object sender, EventArgs e)        {            if (this.Top < 3)                       //当本窗体距屏幕的上边距小于3px时            {                if (this.Handle == MouseNowPosition(Cursor.Position.X, Cursor.Position.Y))//当鼠标在该窗体上时                {                    WindowFlag = 1;                //设定当前的窗体状态                    HideWindow.Enabled = false;     //设定计时器HideWindow为不可用状态                    this.Top = 0;                 //设定窗体上边缘与容器工作区上边缘之间的距离                }                else                              //当鼠标没在窗体上时                {                    WindowFlag = 1;                //设定当前的窗体状态                    HideWindow.Enabled = true;      //启动计时器HideWindow                }            }                                     //当本窗体距屏幕的上边距大于3px时            else            {                //当本窗体在屏幕的最左端或者最右端、最下端时                if (this.Left < 3 || (this.Left + this.Width) > (GetSystemMetrics(0) - 3) || (this.Top + this.Height) > (Screen.AllScreens[0].Bounds.Height - 3))                {                    if (this.Left < 3)              //当窗体处于屏幕左侧时                    {                        if (this.Handle == MouseNowPosition(Cursor.Position.X, Cursor.Position.Y))    //当鼠标在该窗体上时                        {                            this.Height = Screen.AllScreens[0].Bounds.Height - 40;                            this.Top = 3;                            WindowFlag = 2;        //设定当前的窗体状态                            HideWindow.Enabled = false;//设定计时器HideWindow为不可用状态                            this.Left = 0;         //设定窗体的左边缘与容器工作区的左边缘之间的距离                        }                        else                      //当鼠标没在该窗体上时                        {                            WindowFlag = 2;        //设定当前的窗体状态                            HideWindow.Enabled = true;//设定计时器HideWindow为可用状态                        }                    }                    if ((this.Left + this.Width) > (GetSystemMetrics(0) - 3)) //当窗体处于屏幕的最右侧时                    {                        if (this.Handle == MouseNowPosition(Cursor.Position.X, Cursor.Position.Y))//当鼠标处于窗体上时                        {                            this.Height = Screen.AllScreens[0].Bounds.Height - 40;                            this.Top = 3;                            WindowFlag = 3;        //设定当前的窗体状态                            HideWindow.Enabled = false; //设定计时器HideWindow为不可用状态                            this.Left = GetSystemMetrics(0) - this.Width;//设定该窗体与容器工作区左边缘之间的距离                        }                        else                          //当鼠标离开窗体时                        {                            WindowFlag = 3;            //设定当前的窗体状态                            HideWindow.Enabled = true;  //设定计时器HideWindow为可用状态                        }                    }                    //当窗体距屏幕最下端的距离小于3px时                    if ((this.Top + this.Height) > (Screen.AllScreens[0].Bounds.Height - 3))                    {                        if (this.Handle == MouseNowPosition(Cursor.Position.X, Cursor.Position.Y)) //当鼠标在该窗体上时                        {                            WindowFlag = 4;           //设定当前的窗体状态                            HideWindow.Enabled = false;//设定计时器HideWindow为不可用状态                            this.Top = Screen.AllScreens[0].Bounds.Height - this.Height;//设定该窗体与容器工作区上边缘之间的距离                        }                        else                        {                            if ((this.Left > this.Width + 3) && (GetSystemMetrics(0) - this.Right) > 3)                            {                                WindowFlag = 4;           //设定当前的窗体状态                                HideWindow.Enabled = true; //设定计时器HideWindow为可用状态                            }                        }                    }                }            }        }        private void HideWindow_Tick(object sender, EventArgs e)        {            switch (Convert.ToInt32(WindowFlag.ToString())) //判断当前窗体处于那个状态            {                case 1:             //当窗体处于最上端时                       if (this.Top < 3)   //当窗体与容器工作区的上边缘的距离小于5px时                        this.Top = -(this.Height - 2);  //设定当前窗体距容器工作区上边缘的值                    break;                case 2:              //当窗体处于最左端时                    if (this.Left < 3)//当窗体与容器工作区的左边缘的距离小于5px时                        this.Left = -(this.Width - 2); //设定当前窗体据容器工作区左边缘的值                    break;                case 3:             //当窗体处于最右端时                    if ((this.Left + this.Width) > (GetSystemMetrics(0) - 3))  //当窗体与容器工作区的右边缘的距离小于5px时                        this.Left = GetSystemMetrics(0) - 2;    //设定当前窗体距容器工作区左边缘的值                    break;                case 4:             //当窗体处于最低端时                    if (this.Bottom > Screen.AllScreens[0].Bounds.Height - 3)//当窗体与容器工作区的下边缘的距离小于5px时                        this.Top = Screen.AllScreens[0].Bounds.Height - 5;   //设定当前窗体距容器工作区上边缘之间的距离                    break;            }        }        //当窗体离开左右隐藏区域时，窗体回复原有高度        private void MyQQMain_LocationChanged(object sender, EventArgs e)        {            if (this.Left > 3 && this.Right < (GetSystemMetrics(0) - 3))            {                if (this.Height == Screen.AllScreens[0].Bounds.Height - 40)                {                    this.Height = OriHeight;                }            }        }        #endregion