User registration demo program
<! doctype html public "-//w3c//dtd html 4.0//en"
"http://www.w3.org/tr/rec-html140/strict.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=gb2312">
<title>ajax用户注册演示程序</title>
<script language="网页特效" type="text/网页特效">
<!--
//创建函数
function createxmlhttp()
{
var request;
var browser = navigator.appname;
//使用ie，则使用xmlhttp对象
if(browser == "microsoft internet explorer")
{
var arrversions = ["microsoft.xmlhttp", "msxml2.xmlhttp.4.0",
"msxml2.xmlhttp.3.0", "msxml2.xmlhttp","msxml2.xmlhttp.5.0"];
for (var i=0; i < arrversions.length; i++)
{
try
{
//从中找到一个支持的版本并建立xmlhttp对象
request = new activexobject(arrversions[i]);
return request;
}
catch (exception)
{
//忽略，继续
}
}
}
else
{
//否则返回一个xmlhttprequest对象
request = new xmlhttprequest();
if(request.overridemimetype)
{
request.overridemimetype('text/xml');
}
return request;
}
}
//全局xmlhttp对象实例变量
var http = createxmlhttp();
//发送请求
function chkuser()
{
var url = "check.php教程"; //请求"checkusername" servlet
var name = document.getelementbyid("username").value;
url += ("?username="+escape(name)+"&oprate=chkuser");
http.open("get",url,true);
http.onreadystatechange = processhttpresponse;
http.send(null);
return ;
}
//处理响应
function processhttpresponse()
{
if(http.readystate == 4)
{
if(http.status == 200)
{
var xmldocument = http.responsexml;
if(http.responsetext!="该用户名有效，可以使用！")
{
//返回的信息动态显示
document.getelementbyid("showstr").style.display = "";
document.getelementbyid("username").style.background= "#ff0000";
document.getelementbyid("showstr").innertext = http.responsetext;
}
else
{
document.getelementbyid("username").style.background= "#ffffff";
document.getelementbyid("showstr").style.display = "";
document.getelementbyid("showstr").innertext = http.responsetext;
}
}
else
{
alert("你所请求的页面发生异常，可能会影响你浏览该页的信息！");
alert(http.status);
}
}
}
//检验输入密码
function chkpassword()
{
var m=document.form1;
if(m.password.value.length>20 || m.password.value.length<6 )
{
document.getelementbyid("passwordstr").style.display = "";
document.getelementbyid("password").style.background= "#ff0000";
document.getelementbyid("passwordstr").innertext = "对不起,密码必须为英文字母、数字或下划线，长度为6~20!";
}
else
{
document.getelementbyid("password").style.background= "#ffffff";
document.getelementbyid("passwordstr").style.display = "none";
}
}
//验证两次密码是否一致
function chkconfirmpassword()
{
var m=document.form1;
if (m.password.value != m.confirmpassword.value)
{
document.getelementbyid("confirmpasswordstr").style.display = "";
document.getelementbyid("confirmpassword").style.background= "#ff0000";
document.getelementbyid("confirmpasswordstr").innertext = "对不起,密码与重复密码不一致!";
}
else
{
document.getelementbyid("confirmpassword").style.background= "#ffffff";
document.getelementbyid("confirmpasswordstr").style.display = "none";
}
}
//验证email是否有效
function chkemail()
{
var m=document.form1;
var email = m.email.value;
//正则表达式
var regex = /^([a-za-z0-9_-])+@([a-za-z0-9_-])+(.[a-za-z0-9_-])+/;
var flag = regex.test(email);
if(!flag)
{
document.getelementbyid("emailstr").style.display = "";
document.getelementbyid("email").style.background= "#ff0000";
document.getelementbyid("emailstr").innertext = "对不起,邮箱地址无效！";
}
else
{
document.getelementbyid("email").style.background= "#ffffff";
document.getelementbyid("emailstr").style.display = "none";
}
}
//提交检查函数
function submitcheck()
{
var m=document.form1;
if(m.username.value.length==0)
{
alert("对不起,用户名必须为英文字母、数字或下划线，长度为5~20。");
m.username.focus();
return false;
}
if(m.password.value.length==0)
{
alert("对不起,密码必须为英文字母、数字或下划线，长度为5~20。");
m.password.focus();
return false;
}
if (m.password.value != m.confirmpassword.value)
{
alert("对不起,密码与重复密码不一致!");
m.confirmpassword.focus();
return false;
}
if(m.email.value.length==0)
{
alert("对不起,邮箱地址不能为空！！");
m.email.focus();
return false;
}
m.submit();
}
//-->
</script>
<body >
<form name="form1" method="post" action="register.php">
<h3 align="center">ajax用户注册程序</h3>
<table align="center" width="500" border="1" >
<tr>
<td><font color="red">*</font></td>
<td width="100">用户帐号:</td>
<td><input type="text" name="username" maxlength="20" style="background=#ffffff" onblur="chkuser()"></td>
<td><div id="showstr" style="background-color:#ff9900;display:none"></div></td>
</tr>
<tr>
<td><font color="red">*</font></td>
<td>用户密码:</td>
<td align="left"><input type="password" name="password" maxlength="22" style="background=#ffffff" onblur="chkpassword()"/> </td>
<td><div id="passwordstr" style="background-color:#ff9900;display:none"></div></td>
</tr>
<tr>
<td><font color="red">*</font></td>
<td>确认密码:</td>
<td><input type="password" name="confirmpassword" maxlength="20" style="background=#ffffff" onblur="chkconfirmpassword()"/></td>
<td><div id="confirmpasswordstr" style="background-color:#ff9900;display:none"></div></td>
</tr>
<tr>
<td><font color="red">*</font></td>
<td>email:</td>
<td><input type="text" name="email" maxlength="100" style="background=#ffffff" onblur="chkemail()"></td>
<td><div id="emailstr" style="background-color:#ff9900;display:none"></div></td>
</tr>
</table>
<div align="center">
<input type="button" name="ok" value=" 确定 " onclick="submitcheck()">
<input type="reset" name="reset" value=" 取消 ">
</form>
</div>
</body>
</html>reg.php检测程序
<?php
header("content-type:text/html;charset=gb2312");
@mysql教程_connect('localhost','root','ebaeba') or die("数据库教程服务器连接失败");
@mysql_select_db("test") or die("数据库不存在或不可用");
$uname = $_get['username'];
//下面进行数据库查询 查找是不是有这一个用户
//如果没有查找到这个用户名
$sql="select * from t1 where name='".$uname."'";
$query=mysql_query($sql);
$row=mysql_fetch_object($query);
if(strlen($uname)<6||strlen($uname)>20)
{
$msg="用户名必须是6至20个字符.";
}
else
{
if($row==false)
{
$msg="该用户名有效，可以使用！";
}
else
{
$msg="对不起，此用户名已经存在，请更换用户名注册!";
}
}
echo $msg ;
?>
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