<html> <head> <meta charset="UTF-8"> <title></title> <link rel="stylesheet" type="text/css" href="css/reset.css"/> <style type="text/css"> textarea{ resize: none; } </style> </head> <body> <form action="" method="post"> 用户名：<input type="text" id="username" /><br /> 密码：<input type="password" id="password" /><br /> <input type="button" id="btn" value="注册" /> </form> </body></html>xxxxxxxxxxxxxxxxxxxx window.onload=function(){ var oUser=document.getElementById('username'); var oPwd=document.getElementById('password'); var oBtn=document.getElementById('btn'); oBtn.onclick=function(){ var upData=null; var repeat=null; if (oUser.value&&oPwd.value) { if (window.localStorage.getItem('list')) { upData={'username':oUser.value,'password':oPwd.value}; var dataJson=window.localStorage.getItem('list'); dataJson=eval('('+dataJson+')'); for (var i=0;i<dataJson.length;i++) { if (dataJson[i].username==upData.username) { alert('用户名重复'); repeat=1; } } if (repeat==null) { alert('注册成功'); dataJson.push(upData); dataJson=JSON.stringify(dataJson); window.localStorage.setItem('list',dataJson); console.log(window.localStorage.getItem('list')); } } else { upData={'username':oUser.value,'password':oPwd.value}; console.log(upData); var data=[]; data.push(upData); data=JSON.stringify(data); window.localStorage.setItem('list',data); alert('注册成功'); console.log(window.localStorage.getItem('list')); } } } }