Javascript读取cookie函数代码

用法：
一、设置cookie

var cookie = new JSCookie(); 
// 普通设置 
cookie .SetCookie("key1","val1"); 
// 过期时间为一年 
var expire_time = new Date(); 
expire_time.setFullYear(expire_time.getFullYear() + 1); 
cookie .SetCookie("key2","val2",expire_time); 
// 设置域及路径，带过期时间 
cookie .SetCookie("key3","val3",expire_time,".cnblogs.com","/"); 
// 设置带子键的cookie,子键分别是k1,k2,k3 
cookie .SetCookie("key4","k1=1&k2=2&k3=3");

二、读取cookie

// 简单获取 
cookie .GetCookie("key1"); 
cookie .GetCookie("key2"); 
cookie .GetCookie("key3"); 
cookie .GetCookie("key4"); 
// 获取key4的子键k1值 
cookie .GetChild("key4","k1");

三、删除

cookie .Expire("key1"); 
cookie .Expire("key2"); 
cookie .Expire("key3"); 
cookie .Expire("key4");

示例：

<script type="text/javascript"> 
String.prototype.Trim = function() 
{ 
return this.replace(/^\s+/g,"").replace(/\s+$/g,""); 
} 
function JSCookie() 
{ 
this.GetCookie = function(key) 
{ 
var cookie = document.cookie; 
var cookieArray = cookie.split(';'); 
var getvalue = ""; 
for(var i = 0;i<cookieArray.length;i++) 
{ 
if(cookieArray[i].Trim().substr(0,key.length) == key) 
{ 
getvalue = cookieArray[i].Trim().substr(key.length + 1); 
break; 
} 
} 
return getvalue; 
}; 
this.GetChild = function(cookiekey,childkey) 
{ 
var child = this.GetCookie(cookiekey); 
var childs = child.split('&'); 
var getvalue = ""; 
for(var i = 0;i < childs.length;i++) 
{ 
if(childs[i].Trim().substr(0,childkey.length) == childkey) 
{ 
getvalue = childs[i].Trim().substr(childkey.length + 1); 
break; 
} 
} 
return getvalue; 
}; 
this.SetCookie = function(key,value,expire,domain,path) 
{ 
var cookie = ""; 
if(key != null && value != null) 
cookie += key + "=" + value + ";"; 
if(expire != null) 
cookie += "expires=" + expire.toGMTString() + ";"; 
if(domain != null) 
cookie += "domain=" + domain + ";"; 
if(path != null) 
cookie += "path=" + path + ";"; 
document.cookie = cookie; 
}; 
this.Expire = function(key) 
{ 
expire_time = new Date(); 
expire_time.setFullYear(expire_time.getFullYear() - 1); 
var cookie = " " + key + "=e;expires=" + expire_time + ";" 
document.cookie = cookie; 
} 
} 
</script>

用正则的方法读取cookie值
由于asp的cookie是经过url编码的，所以读之前要unescape一下。

下面是我用正则的方法取cookie，包括单值和多值：

/************************************************** 
参数说明： 
sMainName Cookie名 
sSubName Cookie子键名，留空表示单值Cookie 
**************************************************/ 
function GetCookie(sMainName, sSubName) 
{ 
var re = new RegExp((sSubName ? sMainName + "=(?:.*?&)*?" + sSubName + "=([^&;$]*)" : sMainName + "=([^;$]*)"),"i"); 
return re.test(unescape(document.cookie)) ? RegExp["$1"] : ""; 
}