javascript操作cookie

<!--

//学习一下如何利用js来操作cookie

//写入 cookie

//不区分 cookieName 的大小写

//不考虑子键

function WriteCookies(cookieName, cookieValue, expires)

{

if (expires)

{

//指定了 expires

document.cookie =

WriteCookies_GetCookieName(cookieName) + "=" + escape(cookieValue)

+ "; expires=" + xpires.toGMTString();

}

else

{

document.cookie = WriteCookies_GetCookieName(cookieName) + "=" + escape(cookieValue);

}

}

//获取并返回与 cookieName 同名的 cookie 名称，允许大小写不同

//如果不存在这样的 cookie，就返回 cookieName

function WriteCookies_GetCookieName(cookieName)

{

var lowerCookieName = cookieName.toLowerCase();

var cookieStr = document.cookie;

if (cookieStr == "")

{

return cookieName;

}

var cookieArr = cookieStr.split("; ");

var pos = -1;

for (var i=0; i<cookieArr.length; i++)

{

pos = cookieArr[i].indexOf("=");

if (pos > 0)

{

if (cookieArr[i].substring(0, pos).toLowerCase() == lowerCookieName)

{

return cookieArr[i].substring(0, pos);

}

}

}

return cookieName;

}

//获取并返回 cookie 值

//不区分 cookieName 的大小写

//dfltValue 为默认返回值

//不考虑子键

function ReadCookies(cookieName, dfltValue)

{

var lowerCookieName = cookieName.toLowerCase();

var cookieStr = document.cookie;

if (cookieStr == "")

{

return dfltValue;

}

var cookieArr = cookieStr.split("; ");

var pos = -1;

for (var i=0; i<cookieArr.length; i++)

{

pos = cookieArr[i].indexOf("=");

if (pos > 0)

{

if (cookieArr[i].substring(0, pos).toLowerCase() == lowerCookieName)

{

return unescape(cookieArr[i].substring(pos+1, cookieArr[i].length));

}

}

}

return dfltValue;

}

//test all the oper

document.write("写入名称为 cv 的 cookie...<br>");

WriteCookies("test", "test123", null);

document.write("写入名称为 Ab，带失效日期的 cookie...<br>");

var expires = new Date("December 11, 2010");

WriteCookies("singleblue", "test234", expires);

document.write("读取名称为 singleblue 的 cookie..." + ReadCookies("ab", ""));

-->