Ajax实现异步用户名验证功能

function checkAccount(){
var xmlhttp;
var name = document.getElementById("account").value;
if (window.XMLHttpRequest)
 xmlhttp=new XMLHttpRequest();
else
 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
 
xmlhttp.open("GET","login.php?account="+name,true);
xmlhttp.send();
 
xmlhttp.onreadystatechange=function(){
 if (xmlhttp.readyState==4 && xmlhttp.status==200)
  document.getElementById("accountStatus").innerHTML=xmlhttp.responseText;
}

使用Ajax实现异步登陆验证

账 号：


密 码：

<?php
  $con = mysqli_connect("localhost","root","GDHL007","sysu");
 
  if(!empty($_GET[&#39;account&#39;])){
    $sql1 = &#39;select * from login where account = "&#39;.$_GET[&#39;account&#39;].&#39;"&#39;;
    //数据库操作
    $result1 = mysqli_query($con,$sql1);
    if(mysqli_num_rows($result1)>0)
      echo &#39;<font style="color:#00FF00;">该用户存在</font>&#39;;
    else 
      echo &#39;<font style="color:#FF0000;">该用户不存在</font>&#39;;
    mysqli_close($con);
  }else
    echo &#39;<font style="color:#FF0000;">用户名不能为空</font>&#39;;
 
?>