这是利用设置Cookie判断的方法。示例：
<html>
<head>
<script>
function GetCookie(name) {
var arg = name + "=";
var alen = arg.length;
var clen = document.cookie.length;
var i = 0;
while (i < clen) {
var j = i + alen;
if (document.cookie.substring(i, j) == arg)
return getCookieVal(j);
i = document.cookie.indexOf(" ", i) + 1;
if (i == 0) break;
}
return null;
}
function SetCookie(name, value) {
var argv = SetCookie.arguments;
var argc = SetCookie.arguments.length;
var expires = (argc > 2) ? argv[2] : null;
var path = (argc > 3) ? argv[3] : null;
var domain = (argc > 4) ? argv[4] : null;
var secure = (argc > 5) ? argv[5] : false;
document.cookie = name + "=" + escape(value) +
((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +
((path == null) ? "" : ("; path=" + path)) +
((domain == null) ? "" : ("; domain=" + domain)) +
((secure == true) ? "; secure" : "");
}
function DeleteCookie(name) {
var exp = new Date();
exp.setTime(exp.getTime() - 1);
// This cookie is history
var cval = 0;
document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}
//设置cookies时间,自己根据情况设置。
var expDays = 1;
var exp = new Date();
exp.setTime(exp.getTime() + (expDays * 24 * 60 * 60 * 1000));
function amt() {
var count = GetCookie('count');
count = Math.max(1, Number(count) + 1);
SetCookie('count', count, exp);
return count;
}
function getCookieVal(offset) {
var endstr = document.cookie.indexOf(";", offset);
if (endstr == -1) endstr = document.cookie.length;
return unescape(document.cookie.substring(offset, endstr));
}
// IE： 设置为浏览器首页示例
function sethome() {
var link = document.links[0];
if (!link) return;
link.style.behavior = 'url(#default#homepage)';
if (link.setHomePage) link.setHomePage('https://lzw.me');
}
if (amt() == 1) {
alert('首次访问本站');
sethome();
}
</script>
</head>
<body></body>
</html>
