add AlreadyHaveResult function

context.go

@@ -120,7 +120,14 @@ func (c *Context) SetCookie(cookie *http.Cookie) {
 	http.SetCookie(c.Writer, cookie)
 }
 
+func (c *Context) AlreadyHaveResult() (done bool, entry string) {
+	return c.resultentry == "", c.resultentry
+}
+
 func (c *Context) RESULT(output interface{}) error {
+	if c.resultentry == "" {
+		c.resultentry = "RESULT"
+	}
 	var t = reflect.TypeOf(output)
 	defer func(o *interface{}) {
 		b, err := json.Marshal(o)
@@ -149,7 +156,6 @@ func (c *Context) RESULT(output interface{}) error {
 		cost := time.Now().Sub(c.starttime).Milliseconds()
 		noticeStr := fmt.Sprintf("cost: %dms, output: '%s'", cost, string(b))
 		log.NoticefWithDepth(calldepth, noticeStr)
-
 	}(&output)
 
 	if _, ok := t.FieldByName("ErrCode"); !ok {