http.ReadRequest后的Body字段为空，请大家帮忙

```go package main import ( "bufio" "bytes" "fmt" "io" "io/ioutil" "net/http" ) func ParseReq(b []byte) (*http.Request, error) { // func ReadRequest(b *bufio.Reader) (req *Request, err error) { return readRequest(b, deleteHostHeader) } var buf io.ReadWriter buf = new(bytes.Buffer) buf.Write(b) bufr := bufio.NewReader(buf) return http.ReadRequest(bufr) } func main() { context := []byte( `POST http://www.hh.com/login HTTP/1.1 Accept: */* Connection: Keep-Alive Content-Type: application/x-www-form-urlencoded User-Agent: curl/7.47.0 name=bao`) req, err := ParseReq(context) if err != nil { fmt.Println("parse error, ", err) } fmt.Printf("req:---->%#v\n", req) if req.Method == "POST" { fmt.Println("URLEncoded form") body, err := ioutil.ReadAll(req.Body) if err != nil { fmt.Println("readall error， ", err) } fmt.Println(string(body)) //why empty? // err := req.ParseForm() } } ``` 输出结果 ``` req:---->&http.Request{Method:"POST", URL:(*url.URL)(0xc82007a080), Proto:"HTTP/1.1", ProtoMajor:1, ProtoMinor:1, Header:http.Header{"Accept":[]string{"*/*"}, "Connection":[]string{"Keep-Alive"}, "Content-Type":[]string{"application/x-www-form-urlencoded"}, "User-Agent":[]string{"curl/7.47.0"}}, Body:(*struct { http.eofReaderWithWriteTo; io.Closer })(0x91fbb0), ContentLength:0, TransferEncoding:[]string(nil), Close:false, Host:"www.hh.com", Form:url.Values(nil), PostForm:url.Values(nil), MultipartForm:(*multipart.Form)(nil), Trailer:http.Header(nil), RemoteAddr:"", RequestURI:"http://www.hh.com/login", TLS:(*tls.ConnectionState)(nil), Cancel:(<-chan struct {})(nil)} URLEncoded form ``` 不知道为何body为空，看了源码也不清楚，没看懂源码的Body是怎么赋值的