在.Net异步webApi中我们需要记录日志信息,需要获取客户端的ip地址,我们需要使用:HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];来获取客户端的ip地址,在调用异步方法(wait Task.Run(() =>{ }))前需要将主线程中获取的HttpContext.Current对象存至缓存(Cache)中达到多线程共享的目的。如果不是通过主线程获取HttpContext.Current对象将会报空指针异常(NullPointerException)。
1 System.Web.HttpRuntime.Cache.Insert("context", System.Web.HttpContext.Current); //异步调用,HttpContext存入缓存线程共享
2 wait Task.Run(() =>{ })
1 /// <summary>
2 /// 获取客户端IP地址(无视代理)
3 /// </summary>
4 /// <returns>若失败则返回回送地址</returns>
5 public static string GetHostAddress()
6 {
7
8 HttpContext httpContext = HttpContext.Current;
9 if (httpContext == null)
10 httpContext = HttpRuntime.Cache.Get("context") as HttpContext;
11 string userHostAddress = httpContext.Request.ServerVariables["REMOTE_ADDR"];
12
13 if (string.IsNullOrEmpty(userHostAddress))
14 {
15 if (httpContext.Request.ServerVariables["HTTP_VIA"] != null)
16 userHostAddress = httpContext.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString().Split(',')[0].Trim();
17 }
18 if (string.IsNullOrEmpty(userHostAddress))
19 {
20 userHostAddress = httpContext.Request.UserHostAddress;
21 }
22
23 //最后判断获取是否成功,并检查IP地址的格式(检查其格式非常重要)
24 if (!string.IsNullOrEmpty(userHostAddress) && IsIP(userHostAddress))
25 {
26 return userHostAddress;
27 }
28 return "127.0.0.1";
29 }