javascript的cookies和计时小示例

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>

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转载自www.cnblogs.com/lingwang3/p/9818027.html
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