自定义控件之带水印的Textbox

代码地址：

http://download.csdn.net/detail/u010312811/9553195

Windows消息处理：

http://www.cnblogs.com/imstrive/p/5596030.html

1.私有变量

1 //水印文字
2 private string _waterText = String.Empty;
3 //水印颜色
4 private Color _waterColor = Color.DarkGray;

2.属性

 1 /// <summary>
 2 /// 水印文字
 3 /// </summary>
 4 [Description("水印文字"),Category("SLT")]
 5 public string WaterText
 6 {
 7     get { return _waterText; }
 8     set { _waterText = value; }
 9 }
10 /// <summary>
11 /// 水印颜色
12 /// </summary>
13 [Description("水印文字"),Category("SLT")]
14 public Color WaterColor
15 {
16     get { return _waterColor; }
17     set { _waterColor = value; }
18 }

3.Override Methods

1 protected override void WndProc(ref Message m)
2 {
3     base.WndProc(ref m);
4 
5     if (m.Msg == (int)WindowsMessage.WM_PAINT)
6     {
7         WmPaintWater(ref m);
8     }
9 }

4.方法

 1 private void WmPaintWater(ref Message m)
 2 {
 3     //获取控件绑定到的窗口句柄
 4     using (Graphics g = Graphics.FromHwnd(base.Handle))
 5     {
 6         if (string.IsNullOrEmpty(this.Text) && !String.IsNullOrEmpty(this.WaterText) && !this.Focused)
 7         {
 8             TextFormatFlags flags = TextFormatFlags.EndEllipsis | TextFormatFlags.VerticalCenter;
 9             TextRenderer.DrawText(g, WaterText, this.Font, this.ClientRectangle, WaterColor, flags);
10         }
11     }
12 }

 

posted @ 2016-06-18 12:42  imstrive  阅读(357)  评论(0)  编辑  收藏  举报