C# CookieHelper

using System;
using System.Text.RegularExpressions;
using System.Web;

public class CookieHelper
{
    /// <summary>
    /// 清除登录用户的cookie
    /// </summary>
    public static void ClearUserCookie(string cookieDomain, string cookiesName)
    {
        HttpCookie cookie = new HttpCookie(cookiesName);
        cookie.Values.Clear();
        cookie.Expires = DateTime.Now.AddYears(-1);
        //string cookieDomain = ConfigFactory.GetConfig().CookieDomain.Trim();
        if (cookieDomain != string.Empty &&
            HttpContext.Current.Request.Url.Host.IndexOf(cookieDomain, System.StringComparison.Ordinal) > -1
            && IsValidDomain(HttpContext.Current.Request.Url.Host))
            cookie.Domain = cookieDomain;
        HttpContext.Current.Response.AppendCookie(cookie);
    }

    /// <summary>
    /// 读cookie值
    /// </summary>
    /// <param name="strName">名称</param>
    /// <returns>cookie值</returns>
    public static string GetCookie(string strName)
    {
        var httpCookie = HttpContext.Current.Request.Cookies[strName];
        return httpCookie != null ? httpCookie.Value : "";
    }

    /// <summary>
    /// 获得cookie值
    /// </summary>
    /// <param name="cookiesName">Cookie 名称</param>
    /// <param name="strName">项</param>
    /// <returns>值</returns>
    public static string GetCookie(string cookiesName, string strName)
    {
        var httpCookie = HttpContext.Current.Request.Cookies[cookiesName];
        if (httpCookie != null && httpCookie[strName] != null)
        {
            return HttpUtility.UrlDecode(httpCookie.Values[strName]);
        }

        return "";
    }

    /// <summary>
    /// 是否为有效域
    /// </summary>
    /// <param name="host">域名</param>
    /// <returns></returns>
    public static bool IsValidDomain(string host)
    {
        Regex r = new Regex(@"^\d+$");
        if (host.IndexOf(".") == -1)
        {
            return false;
        }
        return !r.IsMatch(host.Replace(".", string.Empty));
    }

    /// <summary>
    /// 写cookie值，不在客户端创建文件，存放在服务器内存中。
    /// </summary>
    /// <param name="strName">名称</param>
    /// <param name="strValue">值</param>
    public static void WriteCookie(string strName, string strValue)
    {
        HttpCookie cookie = HttpContext.Current.Request.Cookies[strName];
        if (cookie == null)
        {
            cookie = new HttpCookie(strName);
        }
        cookie.Value = strValue;
        HttpContext.Current.Response.AppendCookie(cookie);
    }

    /// <summary>
    /// 写cookie值，在客户端创建文件。存放cookie值（单一项值）。
    /// </summary>
    /// <param name="strName">名称</param>
    /// <param name="strValue">值</param>
    /// <param name="cookieDomain">域</param>
    /// <param name="expires">cookie 保存时长 单位分种</param>
    public static void WriteCookie(string strName, string strValue, string cookieDomain, int expires)
    {
        HttpCookie cookie = HttpContext.Current.Request.Cookies[strName] ?? new HttpCookie(strName);
        cookie.Value = strValue;
        //cookie.Expires = DateTime.Now.AddMinutes(expires);
        cookie.Expires = DateTime.Now.AddMinutes(expires);
        cookie.Domain = cookieDomain;
        HttpContext.Current.Response.AppendCookie(cookie);
    }

    /// <summary>
    /// 写cookie值（存放数组形式参数，用于第一次写cookie值，并指定有效时间）
    /// </summary>
    /// <param name="cookieName">cookies名字</param>
    /// <param name="strValuesName">cookie项的名称，cookie[strValuesName][]</param>
    /// <param name="strValue">cookie项的值，cookie[strValuesName][strValue]</param>
    /// <param name="cookieDomain">cookie域属性</param>
    /// <param name="expiresDays">cookies 有效时间 单位天</param>
    public static void WriteCookie(string cookieName, string strValuesName, string strValue, string cookieDomain, int expiresDays)
    {
        HttpCookie cookie = HttpContext.Current.Request.Cookies[cookieName];
        if (cookie == null)
        {
            cookie = new HttpCookie(cookieName);
            cookie.Values[strValuesName] = HttpUtility.UrlEncode(strValue);
        }

        cookie.Values[strValuesName] = HttpUtility.UrlEncode(strValue);
        cookie.Values["expires"] = expiresDays.ToString();
        cookie.Expires = DateTime.Now.AddDays(expiresDays);

        if (cookieDomain != string.Empty
            && HttpContext.Current.Request.Url.Host.IndexOf(cookieDomain) > -1
            && IsValidDomain(HttpContext.Current.Request.Url.Host))
            cookie.Domain = cookieDomain;

        HttpContext.Current.Response.AppendCookie(cookie);
    }

    /// <summary>
    /// 写cookie值（操作已经存在的cookie，存放数组形式参数）
    /// </summary>
    /// <param name="cookieName">cookies名字</param>
    /// <param name="strValuesName">cookie项的名称，cookie[strValuesName][]</param>
    /// <param name="strValue">cookie项的值，cookie[strValuesName][strValue]</param>
    /// <param name="cookieDomain">cookie域属性</param>
    public static void WriteCookie(string cookieName, string strValuesName, string strValue, string cookieDomain)
    {
        HttpCookie cookie = HttpContext.Current.Request.Cookies[cookieName];
        if (cookie == null)
        {
            cookie = new HttpCookie(cookieName);
            cookie.Values[strValuesName] = HttpUtility.UrlEncode(strValue);
        }
        else
        {
            cookie.Values[strValuesName] = HttpUtility.UrlEncode(strValue);

            var httpCookie = HttpContext.Current.Request.Cookies[cookieName];
            if (httpCookie != null && httpCookie["expires"] != null)
            {
                int intExpires = 0;
                if (httpCookie["expires"] != null)
                {
                    try
                    {
                        intExpires = Convert.ToInt32(httpCookie["expires"]);
                    }
                    catch { }
                }

                if (intExpires > 0)
                {
                    cookie.Values["expires"] = intExpires.ToString();
                    cookie.Expires = DateTime.Now.AddMinutes(intExpires);
                }
            }
        }

        if (cookieDomain != string.Empty &&
            HttpContext.Current.Request.Url.Host.IndexOf(cookieDomain, System.StringComparison.Ordinal) > -1 &&
            IsValidDomain(HttpContext.Current.Request.Url.Host))
            cookie.Domain = cookieDomain;

        HttpContext.Current.Response.AppendCookie(cookie);
    }
}