使用正则表达式限制TextBox输入 

 1     /// <summary>
 2     ///  使用正则表达式限制输入
 3     /// </summary>
 4     public class TextBoxRegex : TextBox
 5     {
 6         // 正则表达式，只含有汉字、数字、字母、下划线不能以数字开头 
 7         private const string NamimgPattern = "^(?![0-9])[a-zA-Z0-9_\u4e00-\u9fa5]{1,30}$";
 8 
 9         public TextBoxRegex()
10         {
11             TextChanged += TextBoxRegex_TextChanged;
12         }
13 
14         private void TextBoxRegex_TextChanged(object sender, TextChangedEventArgs e)
15         {
16             //屏蔽非法字符粘贴
17             var textBox = sender as TextBox;
18             if (textBox != null)
19             {
20                 var change = new TextChange[e.Changes.Count];
21                 e.Changes.CopyTo(change, 0);
22 
23                 int offset = change[0].Offset;
24                 if (change[0].AddedLength > 0)
25                 {
26                     if (!Regex.IsMatch(textBox.Text, NamimgPattern, RegexOptions.IgnoreCase))
27                     {
28                         // 不符合正则表达式时移除内容，设置光标位置
29                         textBox.Text = textBox.Text.Remove(offset, change[0].AddedLength);
30                         textBox.Select(offset, 0);
31                     }
32                 }
33             }
34         }
35     }

 

posted @ 2013-12-03 12:14  CandyZkn  阅读(1828)  评论(0)    收藏  举报