关于TextBox设置成MultiLine属性后控制字数的解决方法

使用正则表达式：^(.|\n){0,50}$

例如：

< asp:TextBox ID = " txtPicRemark11 "  runat = " server "  TextMode = " MultiLine " ></ asp:TextBox >
< asp:RegularExpressionValidator ID = " RegularExpressionValidator3 "  runat = " server "  ErrorMessage = " 描述限50个中文字以内 "  ValidationExpression = " ^(.|\n){0,50}$ "  ControlToValidate = " txtPicRemark11 " ></ asp:RegularExpressionValidator >