如何获取当前访问者的IP地址?
编辑:在这里还找到了一个有关IP相关的HTTP头部的有趣问题here。
编辑2:如评论和我提供的链接中所述,HTTP_X_FORWARDED_FOR
标头可能包含由逗号分隔的多个IP地址。我没有遇到过这种情况,但假设我的答案需要一些更正。
我使用此代码来获取IP地址(如果由于某种原因获取失败,则返回IPAddress.None
值):
/// <summary>
/// Gets the IP address of the request.
/// <remarks>
/// This method is more useful than built in because in some cases it may show real user IP address even under proxy.
/// <summary>
/// Gets the IP address of the request.
/// <remarks>
/// This method is more useful than built in because in some cases it may show real user IP address even under proxy.
/// The <see cref="System.Net.IPAddress.None" /> value will be returned if getting is failed.
/// </remarks>
/// </summary>
/// <param name="request">The HTTP request object.</param>
/// <returns></returns>
public static IPAddress GetIp(this HttpRequest request)
{
string ipString;
if (string.IsNullOrEmpty(request.ServerVariables["HTTP_X_FORWARDED_FOR"]))
{
ipString = request.ServerVariables["REMOTE_ADDR"];
}
else
{
ipString = request.ServerVariables["HTTP_X_FORWARDED_FOR"].Split(",".ToCharArray(), StringSplitOptions.RemoveEmptyEntries)
.FirstOrDefault();
}
IPAddress result;
if (!IPAddress.TryParse(ipString, out result))
{
result = IPAddress.None;
}
return result;
}
HttpContext.Current.Request.UserHostAddress;
or
HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
or
HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
Request.UserHostAddress
public String GetIP()
{
string ipString;
if (string.IsNullOrEmpty(Request.ServerVariables["HTTP_X_FORWARDED_FOR"]))
{
ipString = Request.ServerVariables["REMOTE_ADDR"];
}
else
{
ipString = Request.ServerVariables["HTTP_X_FORWARDED_FOR"].Split(",".ToCharArray(), StringSplitOptions.RemoveEmptyEntries).FirstOrDefault();
}
return ipString;
}
首先尝试查找代理IP,如果为空,则可以获取系统IP。
尝试使用以下代码获取用户的外部IP地址。
public static string getExternalIp()
{
try
{
string externalIP;
externalIP = (new WebClient()).DownloadString("http://checkip.dyndns.org/");
externalIP = (new Regex(@"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"))
.Matches(externalIP)[0].ToString();
return externalIP;
}
catch { return null; }
}
X-Forwarded-For
头可以被伪造,因此不要基于它做出任何安全决策。仅在机器位于负载均衡器或反向代理后面时,请检查HTTP_X_FORWARDED_FOR
的值。 - devstuff