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Code for php+ajax to dynamically verify whether the username has been registered
Code for php+ajax to dynamically verify whether the username has been registered
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本文介绍下，php与ajax结合，实现验证用户名是否已注册的代码，有需要的朋友，可以参考下。
1，用户注册页 Login.html
<html>
<head>
<title>用户注册_bbs.it-home.org</title>
<script type="text/javascript">
var xmlHttp;
function createXMLHttpRequest()
{
//在IE下创建XMLHttpRequest对象
try
{
xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e)
{
try
{
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
catch(oc)
{
xmlHttp = null;
}
}
//在Mozilla和Safari等非IE浏览器下创建XMLHTTPRequest对象
if(!xmlHttp && typeof XMLHttpRequest != "undefined")
{
xmlHttp = new XMLHttpRequest();
}
return xmlHttp;
}
//方式请求
function startRequest()
{
//获取用户输入的信息
var UserID = document.getElementById("UserID").value;
//输入的用户名是否为空
if(UserID!="")
{
//创建XMLHttpRequest对象
createXMLHttpRequest();
var url = "Login.php?UserID="+encodeURI(UserID); //指定url
xmlHttp.open("GET",url,true);
xmlHttp.onreadystatechange = handleStateChange; //指定回调函数
xmlHttp.send(null);
}
else
{
alert("请填写您的用户名!");
}
}
function handleStateChange()
{
if(xmlHttp.readyState<4)
{
span.innerHTML="正在读取数据...";
}
if(xmlHttp.readyState==4)
{
if(xmlHttp.status == 200)
{
span.innerHTML=xmlHttp.responseText;
}
else{
alert("错误，请求页面异常!");
}
}
}
</script>
</head>
<body>
<form action="#">
<center>
<h3 id="Ajax-php验证用户名是否可用">Ajax+php验证用户名是否可用</h3>
<table>
<tr>
<td>用户名: <input type="text" name="UserID" id="UserID" onchange="startRequest()" />
<span id="span"></span></td>
</tr>
<tr>
<td>密 码: <input type="text" name="Pwd" id="Pwd"/></td>
</tr>
<tr>
<td>
<br/>
<input type="button" name="Reg" id="Reg" value="注册"/>
<input type="button" name="Log" id="Log" value="登录"/>
</td>
</tr>
</table>
</center>
<form>
</body>
</html>Copy after login 2，注册检测页 Login.php
<?php
//设置PHP的显示语言
header('Content-Type:text/html;charset=UTF-8');
//让程序先等待一秒
sleep(1);
//获取输入的用户名
$tmp=$_GET["UserID"];
$db_host="localhost";
$db_name="canphp";
$db_username="root";
$db_password="rootpass";
$link = mysql_connect($db_host, $db_username,$db_password ) or die ('Can\'t connet db！' . mysql_error());
mysql_select_db($db_name, $link) or die ('Can\'t select db : ' . mysql_error());
$query="select * from cp_user where username='$tmp'";
$result = mysql_query($query) or die ($query.mysql_error());
$rows=mysql_num_rows($result);
if($rows>0)
{ //存在记录
echo "用户名已存在";
}else{
echo("可以注册！");
}
?>Copy after login |
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