JAVA-----Ajax實現註冊使用者名稱唯一性檢查
阿新 • • 發佈：2019-01-02
通過對HTML輸入完畢後，釋放編輯框焦點。執行判斷是否使用者名稱已被註冊的及時提醒操作。
html文字
<%@ page contentType="text/html;charset=GB2312" %> <html> <head> <title>Ajax實現使用者註冊名唯一性檢查</title> <meta http-equiv="content-type" content="text/html; charset=GB2312"> <style type="text/css"> <!-- .style1 {font-size: 12px} .style2 {color: #FF0000} --> </style> </head> <script language="javascript"> var xmlHttpReq=null; function createRequest(){ if(window.XMLHttpRequest){ xmlHttpReq=new XMLHttpRequest(); }else if(window.ActiveXObject){ xmlHttpReq=new ActiveXOject("Microsft.XMLHTTP"); } } function getBackInfo(){ createRequest(); var username=document.getElementById("username").value; if(username.trim().length==0){ document.getElementById("disCheckResult").innerHTML="user no empyt!"; document.getElementById("username").focus(); return false; } if(xmlHttpReq!=null){ var url="checkUser.jsp?username="+username; xmlHttpReq.open("get",url,true); xmlHttpReq.onreadystatechange=disResult; xmlHttpReq.send(null); }else{ alert(":nonononono!!!!"); } } function disResult(){ if(xmlHttpReq.readyState==4){ if(xmlHttpReq.status==200){ alert(xmlHttpReq.responseText); document.getElementById("disCheckResult").innerHTML=xmlHttpReq.responseText; }else{ alert("eorr!"); } } } </script> <body> <form name="form1" method="post" > <table width="100%" border="0" align="center" bgcolor="#0099FF"> <tr> <th colspan="3" scope="col"> 使用者註冊</th> </tr> <tr bgcolor="#FFFFFF"> <th width="36%" rowspan="7" scope="row"></th> <th width="18%" height="46" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">使用者名稱：</font></span></div></th> <td width="46%"><input name="username" type="text" onblur="getBackInfo()" id="username" > <span class="style2">*</span><span id=disCheckResult style="color:red"> </span> </td> </tr> <tr bgcolor="#FFFFFF"> <th height="39" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">密碼：</font></span></div></th> <td><input name="pwd" type="password" id="pwd"> <span class="style2">*</span></td> </tr> <tr bgcolor="#FFFFFF"> <th height="39" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">確認密碼:</font></span></div></th> <td><input type="password" name="pwd1"> <span class="style2">*</span></td> </tr> <tr bgcolor="#FFFFFF"> <th height="39" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">真實姓名：</font></span></div></th> <td><input name="header" type="text"> <span class="style2">*</span></td> </tr> <tr bgcolor="#FFFFFF"> <th height="39" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">電話：</font></span></div></th> <td><input name="phone" type="text"> <span class="style2">*</span></td> </tr> <tr bgcolor="#FFFFFF"> <th height="39" scope="row"><div align="left"> <span style="font-weight: 400"><font size="2">電子郵箱：</font></span></div></th> <td><input name="email" type="text"> <span class="style2">*</span></td> </tr> <tr bgcolor="#FFFFFF"> <th height="37" scope="row"> </th> <td><input type="submit" name="Submit" value="提交"> <input type="reset" name="Reset" value="重填"></td> </tr> </table> </form> </body> </html>
java的程式碼
<%@ page language="java" import="java.util.*,java.sql.*,ajck.aj.*" pageEncoding="utf-8" %> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <% String username=request.getParameter("username"); String sql="select * from users where username=’"+username+"’"; ConnDB conn=new ConnDB(); ResultSet rs= conn.doQuery(sql); if(rs.next()){ out.println("賬號已被註冊"); }else{ out.println("可以註冊"); } %>