求问如图的那种效果是怎样实现的

Question

 public partial class MessageForm : Form
    {
        public MessageForm()
        {
            InitializeComponent();
        }        public Bitmap BackgroundBitmap = null;        private string titleText;
        private string contentText;
        private Color normalTitleColor = Color.FromArgb(0, 0, 0);
        private Font normalTitleFont = new Font("宋体", 12, FontStyle.Regular, GraphicsUnit.Pixel);
        private Color normalContentColor = Color.FromArgb(0, 0, 0);
        private Font normalContentFont = new Font("宋体", 12, FontStyle.Regular, GraphicsUnit.Pixel);        public Rectangle TitleRectangle;
        public Rectangle TitlebarRectangle;
        public Rectangle ContentRectangle;
        public Rectangle CloseBtnRectangle;        private Rectangle WorkAreaRectangle;        private int SavedTop;
        private int currentTop = 1;
        private int intervalValue = 2;        public const int WM_NCLBUTTONDOWN = 0x00A1; //消息:左键点击 winuser.h
        public const int HT_CAPTION = 0x0002; //标题栏        [DllImportAttribute("user32.dll")]
        public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam); //发送消息 //winuser.h 中有函数原型定义
        [DllImportAttribute("user32.dll")]
        public static extern bool ReleaseCapture(); //释放鼠标捕捉 winuser.h
        [DllImportAttribute("user32.dll")] //winuser.h
        private static extern Boolean ShowWindow(IntPtr hWnd, Int32 nCmdShow);        public int CurrentState=0; //0=hide 1=uptoshow 2=showing 3=downtohide                public void SetBackgroundBitmap(Image image, Color transparencyColor)
        {
            BackgroundBitmap = new Bitmap(image);
            Width = BackgroundBitmap.Width;
            Height = BackgroundBitmap.Height;
            Region = BitmapToRegion(BackgroundBitmap, transparencyColor);
        }        public Region BitmapToRegion(Bitmap bitmap, Color transparencyColor)
        {
            if (bitmap == null)
                throw new ArgumentNullException("Bitmap", "Bitmap cannot be null!");            int height = bitmap.Height;
            int width = bitmap.Width;            GraphicsPath path = new GraphicsPath();            for (int j = 0; j < height; j++)
                for (int i = 0; i < width; i++)
                {
                    if (bitmap.GetPixel(i, j) == transparencyColor)
                        continue;                    int x0 = i;                    while ((i < width) && (bitmap.GetPixel(i, j) != transparencyColor))
                        i++;                    path.AddRectangle(new Rectangle(x0, j, i - x0, 1));
                }            Region region = new Region(path);
            path.Dispose();
            return region;
        }        protected void DrawText(Graphics grfx)
        {
            if (titleText != null && titleText.Length != 0)
            {
                StringFormat sf = new StringFormat();
                sf.Alignment = StringAlignment.Near;
                sf.LineAlignment = StringAlignment.Center;
                sf.FormatFlags = StringFormatFlags.NoWrap;
                sf.Trimming = StringTrimming.EllipsisCharacter;
                grfx.DrawString(titleText, normalTitleFont, new SolidBrush(normalTitleColor), TitleRectangle, sf);
            }            if (contentText != null && contentText.Length != 0)
            {
                StringFormat sf = new StringFormat();
                sf.Alignment = StringAlignment.Center;
                sf.LineAlignment = StringAlignment.Center;
                sf.FormatFlags = StringFormatFlags.MeasureTrailingSpaces;
                sf.Trimming = StringTrimming.Word;
                grfx.DrawString(contentText, normalContentFont, new SolidBrush(normalContentColor), ContentRectangle, sf);
            }
        }        protected override void OnPaintBackground(PaintEventArgs e)
        {
            Graphics grfx = e.Graphics;
            grfx.PageUnit = GraphicsUnit.Pixel;            Graphics offScreenGraphics;
            Bitmap offscreenBitmap;            offscreenBitmap = new Bitmap(BackgroundBitmap.Width, BackgroundBitmap.Height);
            offScreenGraphics = Graphics.FromImage(offscreenBitmap);            if (BackgroundBitmap != null)
            {
                offScreenGraphics.DrawImage(BackgroundBitmap, 0, 0, BackgroundBitmap.Width, BackgroundBitmap.Height);
            }            DrawText(offScreenGraphics);            grfx.DrawImage(offscreenBitmap, 0, 0);
        }        public void ShowForm(string ftitletext, string fcontenttext, Rectangle fRegionofFormTitle, Rectangle fRegionofFormTitlebar, Rectangle fRegionofFormContent, Rectangle fRegionofCloseBtn)
        {
            titleText = ftitletext;
            contentText = fcontenttext;
            WorkAreaRectangle = Screen.GetWorkingArea(WorkAreaRectangle);
            this.Top = WorkAreaRectangle.Height + this.Height;
            FormBorderStyle = FormBorderStyle.None;
            WindowState = FormWindowState.Normal;
            this.SetBounds(WorkAreaRectangle.Width - this.Width, WorkAreaRectangle.Height - currentTop, this.Width, this.Height);
            CurrentState = 1;
            timer1.Enabled = true;
            TitleRectangle = fRegionofFormTitle;
            TitlebarRectangle = fRegionofFormTitlebar;
            ContentRectangle = fRegionofFormContent;
            CloseBtnRectangle = fRegionofCloseBtn;            ShowWindow(this.Handle, 4); //#define SW_SHOWNOACTIVATE   4
        }        private void timer1_Tick(object sender, EventArgs e)
        {
            if (CurrentState == 1) 
            {
                this.SetBounds(WorkAreaRectangle.Width - this.Width, WorkAreaRectangle.Height - currentTop, this.Width, this.Height);
                currentTop = currentTop + intervalValue;
                if (this.Top <= WorkAreaRectangle.Height - this.Height)
                {
                    timer1.Enabled = false;
                    CurrentState = 2;
                    timer2.Enabled = true; //显示停留计时
                    currentTop = 1;
                }
            }
            else if (CurrentState==3) 
            {
                this.SetBounds(WorkAreaRectangle.Width - this.Width, SavedTop + currentTop, this.Width, this.Height);
                currentTop = currentTop + intervalValue;
                if (this.Top >= WorkAreaRectangle.Height)
                {
                    timer1.Enabled = false;                    this.Hide();
                    CurrentState = 0;
                    currentTop = 1;
                }
            }
        }        private void TaskbarForm_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                if (TitlebarRectangle.Contains(e.Location)) //单击标题栏时拖动
                {
                    ReleaseCapture(); //释放鼠标捕捉
                    SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0); //发送左键点击的消息至该窗体(标题栏)
                }
                if (CloseBtnRectangle.Contains(e.Location)) //单击Close按钮关闭
                {
                    this.Hide();
                    currentTop = 1;
                }
                if (ContentRectangle.Contains(e.Location )) //单击内容区域
                {
                    //UtilTool.setBool(true);
                    //ElectronRemindForm f = new ElectronRemindForm();
                    //f.ShowDialog();
                }
            }
        }        private void timer2_Tick(object sender, EventArgs e)
        {
            timer2.Enabled = false;
            CurrentState = 1;
            currentTop = 1;
            SavedTop = this.Top;
            CurrentState = 3;
            timer1.Enabled = true;
        }        private void TaskbarForm_MouseMove(object sender, MouseEventArgs e)
        {
            if (ContentRectangle.Contains(e.Location))
            {
                Cursor = Cursors.Hand;
            }
            else
                Cursor = Cursors.Default;
        }
    }
类似于这种右下角弹窗的，改下弹出位置，打下就行了