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

	/// <summary>
	/// Request操作类
	/// </summary>
	public class DNTRequest
	{
		/// <summary>
		/// 判断当前页面是否接收到了Post请求
		/// </summary>
		/// <returns>是否接收到了Post请求</returns>
		public static bool IsPost()
		{
			return HttpContext.Current.Request.HttpMethod.Equals("POST");
		}
		/// <summary>
		/// 判断当前页面是否接收到了Get请求
		/// </summary>
		/// <returns>是否接收到了Get请求</returns>
		public static bool IsGet()
		{
			return HttpContext.Current.Request.HttpMethod.Equals("GET");
		}

		/// <summary>
		/// 返回指定的服务器变量信息
		/// </summary>
		/// <param name="strName">服务器变量名</param>
		/// <returns>服务器变量信息</returns>
		public static string GetServerString(string strName)
		{
			//
			if (HttpContext.Current.Request.ServerVariables[strName] == null)
			{
				return "";
			}
			return HttpContext.Current.Request.ServerVariables[strName].ToString();
		}

		/// <summary>
		/// 返回上一个页面的地址
		/// </summary>
		/// <returns>上一个页面的地址</returns>
		public static string GetUrlReferrer()
		{
			string retVal = null;
    
			try
			{
				retVal = HttpContext.Current.Request.UrlReferrer.ToString();
			}
			catch{}
			
			if (retVal == null)
				return "";
    
			return retVal;

		}
		
		/// <summary>
		/// 得到当前完整主机头
		/// </summary>
		/// <returns></returns>
		public static string GetCurrentFullHost()
		{
			HttpRequest request = System.Web.HttpContext.Current.Request;
			if (!request.Url.IsDefaultPort)
			{
				return string.Format("{0}:{1}", request.Url.Host, request.Url.Port.ToString());
			}
			return request.Url.Host;
		}

		/// <summary>
		/// 得到主机头
		/// </summary>
		/// <returns></returns>
		public static string GetHost()
		{
			return HttpContext.Current.Request.Url.Host;
		}


		/// <summary>
		/// 获取当前请求的原始 URL(URL 中域信息之后的部分,包括查询字符串(如果存在))
		/// </summary>
		/// <returns>原始 URL</returns>
		public static string GetRawUrl()
		{
			return HttpContext.Current.Request.RawUrl;
		}

		/// <summary>
		/// 判断当前访问是否来自浏览器软件
		/// </summary>
		/// <returns>当前访问是否来自浏览器软件</returns>
		public static bool IsBrowserGet()
		{
			string[] BrowserName = {"ie", "opera", "netscape", "mozilla"};
			string curBrowser = HttpContext.Current.Request.Browser.Type.ToLower();
			for (int i = 0; i < BrowserName.Length; i++)
			{
				if (curBrowser.IndexOf(BrowserName[i]) >= 0)
				{
					return true;
				}
			}
			return false;
		}

		/// <summary>
		/// 判断是否来自搜索引擎链接
		/// </summary>
		/// <returns>是否来自搜索引擎链接</returns>
		public static bool  IsSearchEnginesGet()
		{
			string[] SearchEngine = {"google", "yahoo", "msn", "baidu", "sogou", "sohu", "sina", "163", "lycos", "tom"};
			string tmpReferrer = HttpContext.Current.Request.UrlReferrer.ToString().ToLower();
        
            for (int i = 0; i < SearchEngine.Length; i++)
            {
                if (tmpReferrer.IndexOf(SearchEngine[i]) >= 0)
                {
                    return true;
                }
            }

            return false;
		}
       

		/// <summary>
		/// 获得当前完整Url地址
		/// </summary>
		/// <returns>当前完整Url地址</returns>
		public static string GetUrl()
		{
            return HttpContext.Current.Request.Url.PathAndQuery.ToString();
		}
		

		/// <summary>
		/// 获得指定Url参数的值
		/// </summary>
		/// <param name="strName">Url参数</param>
		/// <returns>Url参数的值</returns>
		public static string GetQueryString(string strName)
		{
			if (HttpContext.Current.Request.QueryString[strName] == null)
			{
				return "";
			}
			return HttpContext.Current.Request.QueryString[strName];
		}

		/// <summary>
		/// 获得当前页面的名称
		/// </summary>
		/// <returns>当前页面的名称</returns>
		public static string GetPageName()
		{
			string [] urlArr = HttpContext.Current.Request.Url.AbsolutePath.Split('/');
			return urlArr[urlArr.Length - 1].ToLower();
		}

		/// <summary>
		/// 返回表单或Url参数的总个数
		/// </summary>
		/// <returns></returns>
		public static int GetParamCount()
		{
			return HttpContext.Current.Request.Form.Count + HttpContext.Current.Request.QueryString.Count;
		}


		/// <summary>
		/// 获得指定表单参数的值
		/// </summary>
		/// <param name="strName">表单参数</param>
		/// <returns>表单参数的值</returns>
		public static string GetFormString(string strName)
		{
			if (HttpContext.Current.Request.Form[strName] == null)
			{
				return "";
			}
			return HttpContext.Current.Request.Form[strName];
		}

		/// <summary>
		/// 获得Url或表单参数的值, 先判断Url参数是否为空字符串, 如为True则返回表单参数的值
		/// </summary>
		/// <param name="strName">参数</param>
		/// <returns>Url或表单参数的值</returns>
		public static string GetString(string strName)
		{
			if ("".Equals(GetQueryString(strName)))
			{
				return GetFormString(strName);
			}
			else
			{
				return GetQueryString(strName);
			}
		}

        /// <summary>
        /// 是否为ip
        /// </summary>
        /// <param name="ip"></param>
        /// <returns></returns>
        public static bool IsIP(string ip)
        {
            return Regex.IsMatch(ip, @"^((2[0-4]\d|25[0-5]|[01]?\d\d?)\.){3}(2[0-4]\d|25[0-5]|[01]?\d\d?)$");
        }
		/// <summary>
		/// 获得当前页面客户端的IP
		/// </summary>
		/// <returns>当前页面客户端的IP</returns>
		public static string GetIP()
		{


			string result = String.Empty;

			result = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
			if (null == result || result == String.Empty)
			{
				result = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
			}

			if (null == result || result == String.Empty)
			{
				result = HttpContext.Current.Request.UserHostAddress;
			}

			if (null == result || result == String.Empty || !IsIP(result))
			{
				return "0.0.0.0";
			}

			return result;

		}
        /// <summary>
        /// 保存用户上传的文件
        /// </summary>
        /// <param name="path">保存路径</param>
        public static void SaveRequestFile(string path)
        {
            if (HttpContext.Current.Request.Files.Count > 0)
            {
                HttpContext.Current.Request.Files[0].SaveAs(path);
            }
        }
	}

