title: golang http server,can't get post value
body: <pre><code>func login(rw http.ResponseWriter, req *http.Request) {
      req.ParseForm()
  
      if req.Method == "GET" {
          fmt.Fprintf(rw, "Error Method")
      } else {
          name := strings.TrimSpace(req.FormValue("userid"))
          fmt.Println("userid:", name)
          fmt.Println("pwd:", req.FormValue("pwd"))
          fmt.Fprintf(rw, "welcome back,%s", req.FormValue("userid"))
      }
  }
  </code></pre>
  
  <p>and i using ASIhttprequst send a from,like this.</p>
  
  <pre><code>[self setRequest:[ASIFormDataRequest requestWithURL:[NSURL URLWithString:@"http://127.0.0.1:8080/login"]]];
  [request setPostValue:@"userid" forKey:@"fdfs@jkjlf.cm"];
  [request setPostValue:@"pwd" forKey:@"fdsfdsfdkskfjhds"];
  [request setRequestMethod:@"POST"];
  </code></pre>
  
  <p>i got a null value with req.FormValue("userid")</p>
  
  <p>what happend? and how to fix it?</p>