jQuery+ajax+php实现注册登录功能

html代码，login.html

<form>	<label>用户名</label><input id="user-name" type="text" name="" />	<label>密码</label><input id="user-passWord" type="password" name="" />	<label>验证码</label><input id="code" type="text" name="" /><img src="php/getVerify.php" alt="" />	<div class="clear"></div>	<button type="button" id="login">登录</button>	<button type="button" id="sign">注册</button></form>jquery代码，login.js
$('img').click(function(){		$('img').attr('src','php/getVerify.php?'+Math.random());//刷新验证码	})	$('#login').click(function(){		var username=$('#user-name').val();		var password=$("#user-password").val();		var code=$("#code").val();		if(username!=""&&password!=""&&code.length==4){			$.Ajax({				type:"POST",				url:"php/userLogin.php",				dataType:"JSON",				data:{					"user_name":username,					"password":password,					"code":code				},				success:function(data){					switch(data){						case 1://普通用户							$.cookie("user",username);							$.cookie("limit",0);							window.location.href="index.php";							break;						case 2://管理员用户							$.cookie("user",username);							$.cookie("limit",1);							window.location.href="index.php";							break;						case 3://密码错误							alert("密码错误！");							break;						case 4://用户不存在							alert("该用户不存在！");							break;						case 0://验证码错误							alert("验证码不正确！");							break;					}									}			})		}else{			alert("请检查您的输入！");		}	})	$('#sign').click(function(){		var username=$('#user-name').val();		var password=$("#user-password").val();		var code=$("#code").val();		if(username!=""&&password!=""&&code.length==4){			$.ajax({				type:"POST",				url:"php/addUser.php",				dataType:"JSON",				data:{					"user_name":username,					"password":password,					"code":code				},				success:function(data){					switch(data){						case 1://用户已存在							alert("该用户已存在！请换一个用户名注册。")							break;						case 2://注册成功							alert("注册成功！");							$.cookie("user",username);							$.cookie("limit",0);							window.location.href="index.php";							break;						case 0://验证码错误							alert("验证码不正确！");							break;					}									}			})		}else{			alert("请检查您的输入！");		}	})php代码，userLogin.php
<?phpheader("Content-type: text/html; charset=UTF-8");session_start();$name = $_POST['user_name'];$password=$_POST['password'];$code=$_POST['code'];$con=MySQL_connect('localhost','root','');if(!$con){	die('error:'.mysql_error());}mysql_select_db('db_name');$result=mysql_query("select * from users where user_name='$name'");if($_SESSION['verify']==$code){	if($row=mysql_fetch_array($result)){		if($row['password']==$password){			if($row['power']==0){				echo 1;//普通用户			}else{				echo 2;//管理员用户			}		}else{			echo 3;//密码错误		}	}else{		echo 4;//用户不存在	}}else{	echo 0;//验证码错误}
addUser.php
<?phpheader("Content-type: text/html; charset=UTF-8");session_start();$name = $_POST['user_name'];$password=$_POST['password'];$code=$_POST['code'];$con=mysql_connect('localhost','root','');if(!$con){    die('error:'.mysql_error());}mysql_select_db('db_name');$result=mysql_query("select * from users where user_name='$name'");if($_SESSION['verify']==$code){    if($row=mysql_fetch_array($result)){        echo 1;//用户已存在    }else{//注册成功        mysql_query("insert into `users` (`user_name`,`password`) values ('$name','$password')");        echo 2;    }}else{    echo 0;}