1.cookies示例
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title></title> </head> <head> <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("欢迎 " + user + " 再次访问"); } else { user = prompt("请输入你的名字:",""); if (user!="" && user!=null){ setCookie("username",user,30); } } } </script> </head> <body onload="checkCookie()"></body> </html>
2.计时示例
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title> </title> </head> <body> <p>点击按钮,在等待 3 秒后弹出 "Hello"。</p> <button onclick="myFunction()">点我</button> <script> function myFunction(){ setTimeout(function(){alert("Hello")},3000); } </script> </body> </html>
3.无限计时
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title></title> <script> var c=0; var t; var timer_is_on=0; function timedCount(){ document.getElementById('txt').value=c; c=c+1; t=setTimeout("timedCount()",1000); } function doTimer(){ if (!timer_is_on) { timer_is_on=1; timedCount(); } } </script> </head> <body> <form> <input type="button" value="开始计数!" onClick="doTimer()"> <input type="text" id="txt"> </form> <p>单击按钮,输入框将从0开始一直计数。</p> </body> </html>