注册页面之前先验证用户名是否存在的php代码

reg.php


代码如下:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />
<link rel="stylesheet" type="text/css" href="css/int.css" />
<script type="text/javascript" src="js/func.js"></script>
<style type="text/css">
td{
height:30px;
vertical-align:middle;
align:center;
}
#myText{
width:600px;
}
</style>
<title>注册页面</title>
</head>
<body >
<?php
error_reporting(0);
//不让PHP报告有错语发生。如果不关闭好有类似这的错语 Warning: preg_match() 关闭就不出现了
session_start();
header("Cache-control: private");
$conn = @ mysql_connect("localhost","root","")or die("数据库连接错误");
mysql_select_db("bbs",$conn);
mysql_query("set names utf8");
if($_POST['submit'])
{
$username = $_POST["username"];
$sql="select userName from user_info where userName='$username'";
// echo $sql;
$query=mysql_query($sql);
$rows = mysql_num_rows($query);
if($rows > 0){
echo "<script type='text/javascript'>alert('用户名已存在');location='javascript:history.back()';</script>";
}else{
$user_in = "insert into user_info (username,pass,sex,qq,email,img) values ('$_POST[username]',md5('$_POST[pass]'),'$_POST[sex]','$_POST[qq]','$_POST[email]','$_POST[img_select]')";
//echo $user_in;
mysql_query($user_in);
echo "<script type='text/javascript'>alert('写入成功！！');location.href='login.php';</script>";
}
//javascript:history.go(-1)
}
?>
<form action="reg.php" name="reg_form" method="post" onsubmit="return check_reg()">
<table name="reg_table" align="left">
<tr>
<td>用户：</td><td><input id="username" name="username" class="myText" type="text" maxlength="12" /></td>
</tr>
<tr> <!--性别：0 保密 1 女 2 男-->
<td > 性别：</td>
<td>女<input type="radio" value="1" name="sex"/>
男<input type="radio" value="2" name="sex" />
保密<input type="radio" value="0" name="sex" checked/></td>
</tr>
<tr>
<td>密码：</td><td><input name="pass" class="myText" type="password" onblur="check_len(this)"/><span id="show_pass" style="color:red;"></span></td>
</tr>
<tr>
<td>重复密码：</td><td><input name="repass" class="myText" type="password" onblur="check_pass(this)" /><span id="show_repass" style="color:red;"></span></td>
</tr>
<tr>
<td>QQ：</td><td><input type="text" class="myText" name="qq" onblur="check_qq(this)"/><span style="color:red;" id="show_qq"></span></td>
</tr>
<tr>
<td>邮箱：</td><td><input type="text" class="myText" name="email" onblur="check_email(this)"/><span id="show_e" style="color:red;"></span></td>
</tr>
<tr>
<td height="60">头像：</td>
<td>
<select name="img_select" onchange="img_change(this)">
<option value="101" >女 001</option>
<option value="102" >女 002</option>
<option value="103" >女 003</option>
<option value="104" >女 004</option>
<option value="105" >男 001</option>
<option value="106" >男 002</option>
<option value="107" >男 003</option>
<option value="108" >男 004</option>
</select>
<img src="/bbs/img/101.gif" id="tx_change" style="width:50px; height:65px;" alt=""/>
</td>
</tr>
<tr height="20" align="justify">
<td align="right" ><input type="submit" value="注册" name="submit" style="margin-right:5px;"/></td>
<td><input type="reset" value="重置" name="reset" style="margin-left:5px;"/></td>
</tr>
<tr>
<td colspan="2">我已有账号现在<a href="login.php">登录</a></td>
</tr>
</table>
</form>
</body>
</html>

func.js


代码如下:

//根据下拉框变换图片
function img_change(thisObj){
var imgsrc = "/bbs/img/"+ thisObj.value+".gif";
document.getElementById("tx_change").src=imgsrc;
}
//检查是否都符合 注册 要求
function check_reg()
{
if(check_len() && check_pass() && check_email() && check_qq())
{
return true;
}else{
return false;
}
}
//检查密码长度不能少于6
function check_len(thisObj){
if(thisObj.value.length==0)
{
document.getElementById('show_pass').innerHTML="密码不能为空";
return false;
}else{
if (thisObj.value.length<6)
{
document.getElementById('show_pass').innerHTML="密码长度不少于6";
return false;
}
document.getElementById('show_pass').innerHTML="";
return true;
}
}
//检查俩次密码输入是否一致
function check_pass(thisObj){
var psw=document.getElementById('pass');
if(psw.value.length==0)
{
document.getElementById('show_pass').innerHTML="密码不能为空";
return false;
}else{
document.getElementById('show_pass').innerHTML="";
if (thisObj.value!=psw.value)
{
document.getElementById('show_repass').innerHTML="两次密码输入不正确";
return false;
}
document.getElementById('show_repass').innerHTML="";
return true;
}
}
//检查email是否正确
function check_email(thisObj){
var reg=/^([a-zA-Z\d][a-zA-Z0-9_]+@[a-zA-Z\d]+(\.[a-zA-Z\d]+)+)$/gi;
var rzt=thisObj.value.match(reg);
if(thisObj.value.length==0){
document.getElementById('show_e').innerHTML="Email不能为空";
return false;
}else{
if (rzt==null)
{
document.getElementById('show_e').innerHTML="Email地址不正确";
return false;
}
document.getElementById('show_e').innerHTML="";
return true;
}
}
//检查qq格式是否正确
function check_qq(thisObj){
var qq=document.getElementById('qq').value;
var reg=/^\d+$/;
if(qq.search(reg))
{
document.getElementById('show_qq').innerHTML=" QQ 只能为数字";
return false;
}else{
document.getElementById('show_qq').innerHTML="";
return true ;
}
}

作者： sweet__smile