文本框在鼠标离开时触发JS方法
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="textBox.WebForm1" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title></title> <script type="text/javascript"> function validate() { var name = document.getElementById("txtName"); if (name.value == 2) { alert("你必须不是二!"); name.focus(); return false; } return true; } </script></head><body> <form id="form1" runat="server"> <div> <asp:TextBox ID="txtName" onblur="validate();" runat="server" /> </div> </form></body></html>