php ajax 局部刷新注册验证的例子

// JavaScript Document
var xmlHttp;
function S_xmlhttprequest()
{
xmlHttp=null;
if (window.XMLHttpRequest)
{// code for IE7, Firefox, Opera, etc.
xmlHttp=new XMLHttpRequest();
}
else if (window.ActiveXObject)
{// code for IE6, IE5
xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
}
}
function getName(name)
{
if(name = document.myform.name.value)
{
S_xmlhttprequest();
xmlHttp.open("get","data.php?name="+name,true);
xmlHttp.onreadystatechange = byname;
xmlHttp.send(null);
}
}
function byname()
{
if(xmlHttp.readyState ==1)
{
document.getElementById('name').innerHTML = "loading....";
}
if(xmlHttp.readyState == 4)
{
if(xmlHttp.status == 200)
{
var name = xmlHttp.responseText;
document.getElementById('name').innerHTML = name;
}
}
}
function getEmail(email)
{
var email = document.myform.email.value;
if(email =="")
{
alert("用户名不能为空");
document.myform.email.focus();
return false;
}
else
{
S_xmlhttprequest();
xmlHttp.open("get","data.php?email="+email,true);
xmlHttp.onreadystatechange = byemail;
xmlHttp.send(null);
}
}
function byemail()
{
if(xmlHttp.readyState ==1)
{
document.getElementById('email').innerHTML = "loading....";
}
if(xmlHttp.readyState == 4)
{
if(xmlHttp.status == 200)
{
var email = xmlHttp.responseText;
document.getElementById('email').innerHTML = email;
}
}
}

2、register.php文件

注册页面_bbs.it-home.org






用户名:

*用户名必填*


邮箱:

*邮箱必填*

3、data.php页面，用于ajax查询数据库。

sleep(1);
$connt = mysql_connect("localhost","root","123456");
mysql_select_db('test',$connt );
mysql_query("set names 'gb2312'");
if($_GET['name'])
{
$name = $_GET['name'];
$sql = "select * from test where name='$name'";
$restul = mysql_query($sql);
$array = mysql_fetch_row($restul);
// print_r($array);
if(is_array($array))
{
echo "该用户名已经存在";
}
else
{
echo "该用户名可以用";
}
}
if($_GET['email'])
{
$name = $_GET['email'];
$sql = "select * from test where email='$email'";
$restul = mysql_query($sql);
$array = mysql_fetch_row($restul);
// print_r($array);
if(is_array($array))
{
echo "该邮箱已存在";
}
else
{
echo "该邮箱可以用";
}
}
?>

由此即可实现用户注册时局部刷新的功能了。