jquery ajax显示对号和错号，用于验证输入验证码是否正确

  
    

   
     
<script src="js/j.js"></script>
   
     
<script>
   
     
$(document).ready(function(e) {
   
     
 $('#yes').hide();
   
     
 $('#no').hide();
   
     
 $('input[name=gcode]').keyup(function(){
   
     
 if($(this).val().length==4){
   
     
 $.post('gbook.php',{cc:$('input[name=gcode]').val()},function(msg){
   
     
 
   
     
 if(msg=='yes'){
   
     
 $('#no').hide();
   
     
 $('#yes').show();
   
     
 }else{
   
     
 $('#yes').hide();
   
     
 $("#no").show();
   
     
 }
   
     
 });
   
     
 }
   
     
 });
   
     
});
   
     
</script>
  
    

首先引入jquery

   
     

    
      
.sl-error-verifycode {
    
      
 background-image: url("images/icons.png");
    
      
 background-position: -26px 0;
    
      
 background-repeat: no-repeat;
    
      
 display: block;
    
      
 font-size: 18px;
    
      
 height: 23px;
    
      
 line-height: 20px;
    
      
 margin-left: 180px;
    
      
 margin-top: -25px;
    
      
 position: relative;
    
      
 text-align: center;
    
      
 width: 20px;
    
      
 z-index: 2;
    
      
}
    
      
.sl-correct-verifycode {
    
      
 background-image: url("images/icons.png");
    
      
 background-position: -50px 0;
    
      
 background-repeat: no-repeat;
    
      
 display: block;
    
      
 font-size: 18px;
    
      
 height: 23px;
    
      
 line-height: 20px;
    
      
 margin-left: 180px;
    
      
 margin-top: -25px;
    
      
 position: relative;
    
      
 text-align: center;
    
      
 width: 20px;
    
      
 z-index: 2;
    
      
}
   
     

验证码的html 代码

   
     

    
      
 <tr>
    
      
 <td height="40" align="right">验证码：</td>
    
      
 <td height="40"><span class="addred">*</span></td>
    
      
 <td height="40">
    
      
 <input type="text" name="gcode" id="textfield7" class="txtlist">
    
      
<span id="yes" class="sl-correct-verifycode"></span><span id="no" class="sl-error-verifycode"></span>
    
      
 <img style="float:right; margin-top:-25px; margin-right:300px;" align="middle" src="inc/cc.php" onClick="this.src='inc/cc.php?'+new Date" title="点击换一张图片" width="100px"></td>
    
      
 </tr>
   
     

gbook.php

   
     

    
      
<?php
    
      
session_start();
    
      
if(isset($_POST['cc'])){
    
      
 $cc = strtolower($_POST['cc']);
    
      
 $ss = strtolower($_SESSION['code']);
    
      
 if($cc==$ss){
    
      
 echo "yes";
    
      
 }else{
    
      
 echo "no"; 
    
      
 }
    
      
}
   
     

注意图片一定要引入

来自为知笔记(Wiz)