重写TextBox实现显示提示信息

  1     /// <summary>
  2     /// TextBox提示信息
  3     /// </summary>
  4     /// <author>Tim_et</author>
  5     /// <description>为TextBox提供提示信息，有ToolTip方式，边框提示方式，ErrorProvider方式</description>
  6     [ToolboxItem(true)]
  7     [ToolboxBitmap("information.bmp")]
  8     public partial class TipTextBox : TextBox
  9     {
 10         /// <summary>
 11         /// 窗体句柄绘制
 12         /// </summary>
 13         /// <param name="hWnd"></param>
 14         /// <returns></returns>
 15         [System.Runtime.InteropServices.DllImport("user32.dll")]
 16         static extern IntPtr GetWindowDC(IntPtr hWnd);
 17         [System.Runtime.InteropServices.DllImport("user32.dll")]
 18         static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);
 19 
 20 
 21         //private string pattern = @"^[0-9]*$";
 22         private int WM_PAINT = 0xF;
 23         private string tipText;
 24         private Color tipTextColor = Color.DarkGray;
 25         private bool isShowTipText = false;
 26         private Color tipBorderColor = Color.Red;
 27         private Color normalBorderColor = Color.DimGray;
 28         private bool isShowTipBorder = false;
 29         #region errorProvider
 30         private ErrorProvider errorProvider;
 31         private string errorMsg = string.Empty;
 32         /// <summary>
 33         /// 错误信息
 34         /// </summary>
 35         public string ErrorMsg
 36         {
 37             get { return errorMsg; }
 38             set { errorMsg = value; }
 39         }
 40         /// <summary>
 41         /// 闪烁风格
 42         /// </summary>
 43         public ErrorBlinkStyle BlinkStyle
 44         {
 45             get { return errorProvider.BlinkStyle; }
 46             set { errorProvider.BlinkStyle = value; }
 47         }
 48         /// <summary>
 49         /// 闪烁间隔
 50         /// </summary>
 51         public int BlinkRate
 52         {
 53             get { return errorProvider.BlinkRate; }
 54             set { errorProvider.BlinkRate = value; }
 55         }
 56 
 57         #endregion
 58 
 59 
 60         /// <summary>
 61         /// 提示信息内容
 62         /// </summary>
 63         [DefaultValue("")]
 64         public string TipText
 65         {
 66             get { return tipText; }
 67             set
 68             {
 69                 tipText = value;
 70                 base.Invalidate();
 71             }
 72         }
 73         /// <summary>
 74         /// 提示信息的颜色
 75         /// </summary>
 76         [DefaultValue(typeof(Color), "DarkGray")]
 77         public Color TipTextColor
 78         {
 79             get { return tipTextColor; }
 80             set
 81             {
 82                 tipTextColor = value;
 83                 base.Invalidate();
 84             }
 85         }
 86         /// <summary>
 87         /// 是否显示提示信息
 88         /// </summary>
 89         public bool IsShowTipText
 90         {
 91             get { return isShowTipText; }
 92             set { isShowTipText = value; }
 93         }
 94         /// <summary>
 95         /// 提示边框颜色
 96         /// </summary>
 97         public Color TipBorderColor
 98         {
 99             get { return tipBorderColor; }
100             set { tipBorderColor = value; }
101         }
102         /// <summary>
103         /// 正常时颜色（无需提示时）
104         /// </summary>
105         public Color NormalBorderColor
106         {
107             get { return normalBorderColor; }
108             set { normalBorderColor = value; }
109         }
110         /// <summary>
111         /// 是否显示提示边框
112         /// </summary>
113         public bool IsShowTipBorder
114         {
115             get { return isShowTipBorder; }
116             set { isShowTipBorder = value; }
117         }
118 
119         public TipTextBox()
120             : base()
121         {
122             errorProvider = new ErrorProvider();
123         }
124 
125 
126         protected override void WndProc(ref Message m)
127         {
128 
129             base.WndProc(ref m);
130 
131             if (m.Msg == WM_PAINT || m.Msg == 0x133)
132             {
133                 if (isShowTipBorder)
134                 {
135                     IntPtr hDC = GetWindowDC(m.HWnd);
136                     if (hDC.ToInt32() == 0)
137                     {
138                         return;
139                     }
140                     
141                     System.Drawing.Pen pen = new Pen(this.tipBorderColor, 1);
142                     if (this.Focused || this.Text.Length > 0)
143                     {
144                         pen.Color = normalBorderColor;
145                     }
146                     //绘制边框 
147                     System.Drawing.Graphics g = Graphics.FromHdc(hDC);
148                     g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
149                     g.DrawRectangle(pen, 0, 0, this.Width - 1, this.Height - 1);
150                     pen.Dispose();
151                     m.Result = IntPtr.Zero;
152                     //释放 
153                     ReleaseDC(m.HWnd, hDC);
154                 }
155 
156                 if (IsShowTipText)
157                 {
158                     ///使用TextRenderer绘制底层的显示字样
159                     using (Graphics graphics = Graphics.FromHwnd(this.Handle))
160                     {
161                         if (string.IsNullOrEmpty(this.Text) && !string.IsNullOrEmpty(TipText) && !Focused)
162                         {
163                             TextFormatFlags textFormatFlags = TextFormatFlags.EndEllipsis | TextFormatFlags.VerticalCenter;
164                             if (this.RightToLeft == RightToLeft.Yes)
165                             {
166                                 textFormatFlags |= TextFormatFlags.RightToLeft | TextFormatFlags.Right;
167                             }
168                             TextRenderer.DrawText(graphics, TipText, this.Font, base.ClientRectangle, TipTextColor, textFormatFlags);
169                         }
170                     }
171                 }
172 
173             }
174         }
175 
176         /// <summary>
177         /// 显示errorProvider
178         /// </summary>
179         /// <param name="msg"></param>
180         public void ShowErrorProvider(string msg)
181         {
182             errorProvider.SetError(this, msg);
183         }
184 
185         private void InitializeComponent()
186         {
187             this.SuspendLayout();
188             this.ResumeLayout(false);
189 
190         }
191     }