简单教程
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代码编辑器：
<!DOCTYPE html> <meta charset="utf-8"> <script> function setCookie(cname,cvalue,exdays){ var d = new Date(); d.setTime(d.getTime()+(exdays*24*60*60*1000)); var expires = "expires="+d.toGMTString(); document.cookie = cname+"="+cvalue+"; "+expires; } function getCookie(cname){ var name = cname + "="; var ca = document.cookie.split(';'); for(var i=0; i<ca.length; i++) { var c = ca[i].trim(); if (c.indexOf(name)==0) return c.substring(name.length,c.length); } return ""; } function checkCookie(){ var user=getCookie("username"); if (user!=""){ alert("Welcome again " + user); } else { user = prompt("Please enter your name:",""); if (user!="" && user!=null){ setCookie("username",user,30); } } } </script> <body onload="checkCookie()"></body>
运行结果：