cookies.txt

描述了cookie的使用技巧,和平常之中在编程方面的基本应用

    /// 存Cookie
    /// Json Lee 2007-09-24
    /// </summary>
    /// <param name="strName">名称</param>
    /// <param name="strValue">值</param>
    /// <returns></returns>
    public void SetCookie(string cookieName, string cookieValue)
    {
        SetCookie(cookieName, cookieValue, 60);
    }

    /// <summary>
    /// 清除Cookie
    /// </summary>
    /// <param name="strName">名称</param>
    /// <returns></returns>
    public void ClearCookie(string cookieName)
    {
        SetCookie(cookieName,"",-5);
    }

    /// <summary>
    /// 取Cookie
    /// Json Lee 2007-09-24
    /// </summary>
    /// <param name="strName">名称</param>
    /// <param name="strDefaultValue">当没有值的时候的默认值</param>
    /// <returns></returns>
    public string GetCookie(string cookieName, string defaultValue)
    {
        cookieName = cookieName.ToLower();
        string strResult = defaultValue;
        try
        {
            if (HttpContext.Current.Request.Cookies != null)
            {
                if (HttpContext.Current.Request.Cookies[cookieName] != null)
                {
                    strResult = HttpContext.Current.Request.Cookies[cookieName].Value;
                }
            }
        }
        catch (Exception ex)
        {
            this.WriteWrongLog(ex);
        }

        return strResult;
    }

    /// <summary>
    /// 取Cookie
    /// Json Lee 2007-09-24
    /// </summary>
    /// <param name="strName">名称</param>
    /// <returns></returns>
    public string GetCookie(string strName)
    {
        return GetCookie(strName, "");
    }
    #endregion
Cookie存取看起来的确很简单，而在.NET里面好像更简单。
但是......................
往往简单的东西经常出现一些问题，让人找不到原因。
我之前这里出现的问题就是，在写Cookie的时候，没有处理旧的同名Cookie，例如：第一次登录的时候写入 Cookie username=jsonlee 和 password=123456
有时候有可能会在未退出的情况下重新登录一下，这样就会再次写入同样的Cookie，但这样的情况，好像没有把原来的覆盖(我用 IECookies 这个工具看到的)，而是新加入一个同名的。这样一来明显问题就存在了。
所以我在SetCookie的方法里面加入了 
//删除旧的同名Cookie        
HttpContext.Current.Response.Cookies.Remove(cookieName);

function SetCookie(name,value)//两个参数，一个是cookie的名子，一个是值
{
    var Days = 30; //此 cookie 将被保存 30 天
    var exp  = new Date();    //new Date("December 31, 9998");
    exp.setTime(exp.getTime() + Days*24*60*60*1000);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
}
function getCookie(name)//取cookies函数        
{
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
     if(arr != null) return unescape(arr[2]); return null;

}
function delCookie(name)//删除cookie
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}



SetCookie ("xiaoqi", "3")
alert(getCookie('xiaoqi'));
</script>

 



一个非常实用的javascript读写Cookie函数

一个非常实用的javascript读写Cookie函数  
function  GetCookieVal(offset)
//获得Cookie解码后的值
{
var  endstr  =  documents.cookie.indexOf  (";",  offset);
if  (endstr  ==  -1)
endstr  =  documents.cookie.length;
return  unescape(documents.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  ));
documents.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);
documents.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  =  documents.cookie.length;
var  i  =  0;
while  (i  <  clen)
{
var  j  =  i  +  alen;
if  (documents.cookie.substring(i,  j)  ==  arg)
return  GetCookieVal  (j);
i  =  documents.cookie.indexOf("  ",  i)  +  1;
if  (i  ==  0)  break;
}
return  null;
}



 



<SCRIPT  language="javascript">
<!--
function  openpopup(){
url="popup.htm"
window.open("gonggao.htm","gonggao","width=260,height=212,left=200,top=0")
}

function  get_cookie(Name)  {
var  search  =  Name  +  "="
var  returnvalue  =  "";
if  (documents.cookie.length  >  0)  {
offset  =  documents.cookie.indexOf(search)
if  (offset  !=  -1)  {
offset  +=  search.length
end  =  documents.cookie.indexOf(";",  offset);
if  (end  ==  -1)
end  =  documents.cookie.length;
returnvalue=unescape(documents.cookie.substring(offset,  end))
}
}
return  returnvalue;
}

function  helpor_net(){
if  (get_cookie('popped')==''){
openpopup()
documents.cookie="popped=yes"
}
}
helpor_net()
//-->
</SCRIPT>



 



如果点了确定，只要不清cookie，以后访问都不会再提示，如果不点确定则每次都会提示。放在js文件里，全站包含

<SCRIPT LANGUAGE="JavaScript">
<!--
var the_cookie = document.cookie;
var broken_cookie = the_cookie.split(":");
var the_visiteraccepted = unescape(broken_cookie[1]);
//
if (the_visiteraccepted=="undefined"){
        var tmp=confirm('中国人何时何地。');
        if(tmp==false){
                window.close();
        }else{
                var the_visiteraccepted = 1;          
        var the_cookie = "ILoveChina=visiteraccepted:" + escape(the_visiteraccepted);                                 
        document.cookie = the_cookie;
        }
}
//-->
</SCRIPT>