<!doctype html> <html> <head> <meta charset="utf-8"> <title>无标题文档</title> <script> window.onload = function () { var ologin = document.getElementById('login'); var odel = document.getElementById('del'); var ousername = document.getElementById('username'); if(getcookie('username')) { ousername = getcookie('username'); } ologin.onclick = function() { alert('登陆成功') setcookie('username',ousername.value,5); } odel.onclick = function () { removecookie('username'); ousername.value = ''; } function getcookie (key) { var arr1 = document.cookie.split(';'); for(var i = 0; i < arr1.length; i++) { var arr2 = arr1[i].split('='); if(key == arr2[0]) { return decodeURI(arr2[1]); } } } function getcookie (key) { var arr1 = document.cookie.split(';'); for(var i = 0; i < arr1.length; i++) { var arr2 = arr1[i].split('='); if(key == arr2[0]) { return decodeURI(arr2[1]); } } } function setcookie(key,value,t) { var oDate = new Date(); oDate.setDate(oDate.getDate()+t); document.cookie = key + ':' + value + ';expires =' + oDate.toGMTString(); } function removecookie(key) { setcookie(key,'',-1); } }; </script> </head> <body> <input type="text" id="username"> <input type="button" id="login" value="登陆"> <input type="button" id="del" value="删除"> </body> </html>