1 public class IPHelper
2 {
3 public static string GetVisitorsIPAddress()
4 {
5 string result = String.Empty;
6
7 result = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
8
9 // 如果使用代理,获取真实IP
10 if (result != null && result.IndexOf(".") == -1) //没有“.”肯定是非IPv4格式
11 result = null;
12 else if (result != null)
13 {
14 if (result.IndexOf(",") != -1)
15 {
16 //有“,”,估计多个代理。取第一个不是内网的IP。
17 result = result.Replace(" ", "").Replace("'", "");
18 string[] temparyip = result.Split(",;".ToCharArray());
19 for (int i = 0; i < temparyip.Length; i++)
20 {
21 if (IsIPAddress(temparyip[i])
22 && temparyip[i].Substring(0, 3) != "10."
23 && temparyip[i].Substring(0, 7) != "192.168"
24 && temparyip[i].Substring(0, 7) != "172.16.")
25 {
26 return temparyip[i]; //找到不是内网的地址
27 }
28 }
29 }
30 else if (IsIPAddress(result)) //代理即是IP格式
31 return result;
32 else
33 result = null; //代理中的内容 非IP,取IP
34 }
35 if (null == result || result == String.Empty)
36 result = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
37
38 if (result == null || result == String.Empty)
39 result = System.Web.HttpContext.Current.Request.UserHostAddress;
40
41 return result;
42 }
43
44 /// <summary>
45 /// 判断是否是IP地址格式 0.0.0.0
46 /// </summary>
47 /// <param name="str1">待判断的IP地址</param>
48 /// <returns>true or false</returns>
49 private static bool IsIPAddress(string str1)
50 {
51 if (str1 == null || str1 == string.Empty || str1.Length < 7 || str1.Length > 15) return false;
52
53 string regformat = @"^\d{1,3}[\.]\d{1,3}[\.]\d{1,3}[\.]\d{1,3}$";
54
55 Regex regex = new Regex(regformat, RegexOptions.IgnoreCase);
56 return regex.IsMatch(str1);
57 }
58 }