一个非常实用的javascript读写Cookie函数

javascript读写删除cookie的操作.

function GetCookieVal(offset)

//获得Cookie解码后的值

{

var endstr = document.cookie.indexOf (";", offset);

if (endstr == -1)

endstr = document.cookie.length;

return unescape(document.cookie.substring(offset, endstr));

}

---------------------------

function SetCookie(name, value)

//设定Cookie值

{

var expdate = new Date();

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;

if(expires!=null) expdate.setTime(expdate.getTime() + ( expires * 1000 ));

document.cookie = name + "=" + escape (value) +((expires == null) ? "" : ("; expires="+ expdate.toGMTString()))

+((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain))

+((secure == true) ? "; secure" : "");

}

---------------------------------

function DelCookie(name)

//删除Cookie

{

var exp = new Date();

exp.setTime (exp.getTime() - 1);

var cval = GetCookie (name);

document.cookie = name + "=" + cval + "; expires="+ exp.toGMTString();

}

------------------------------------

function GetCookie(name)

//获得Cookie的原始值

{

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;

}