获取客户端的IP地址

/// <summary>

/// 获取客户端的IP地址

/// </summary>

/// <returns></returns>

public static string ClientIP()

{

    string result = String.Empty;

    result = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];

    if (result != null && result != String.Empty)

    {

        //可能有代理 

        if (result.IndexOf(".") == -1)

            //没有"."肯定是非IPv4格式 

            result = null;

        else

        {

            if (result.IndexOf(",") != -1)

            {

                //有","，估计多个代理。取第一个不是内网的IP。 

                result = result.Replace(" ", "").Replace("", "");

                string[] temparyip = result.Split(",;".ToCharArray());

                for (int i = 0; i < temparyip.Length; i++)

                {

                    if (IsIPAddress(temparyip[i]) && temparyip[i].Substring(0, 3) != "10." && temparyip[i].Substring(0, 7) != "192.168" && temparyip[i].Substring(0, 7) != "172.16.")

                    {

                        return temparyip[i];//找到不是内网的地址 

                    }

                }

            }

            else if (IsIPAddress(result)) //代理即是IP格式 

                return result;

            else

                result = null;//代理中的内容 非IP，取IP 

        }

    }

    string IpAddress =

    (HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null &&

    HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != String.Empty) ? HttpContext.Current.Request.ServerVariables

    ["HTTP_X_FORWARDED_FOR"] : HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];

    if (null == result || result == String.Empty)

        result = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];

    if (result == null || result == String.Empty)

        result = HttpContext.Current.Request.UserHostAddress;

    return result;

}

/// <summary>

/// ip判断

/// </summary>

/// <param name="str1"></param>

/// <returns></returns>

private static bool IsIPAddress(string str1)

{

    if (str1 == null || str1 == string.Empty || str1.Length < 7 || str1.Length > 15)

        return false;

    string regformat = @"^\d{1,3}[\.]\d{1,3}[\.]\d{1,3}[\.]\d{1,3}$";

    Regex regex = new Regex(regformat, RegexOptions.IgnoreCase);

    return regex.IsMatch(str1);

}