3 Return
Lunny Xiao edited this page 2017-04-11 14:52:23 +08:00

Return Values

According func or method's return values, returnHandle will automatically write content to ResponseWriter.

The return value could be below types or interfaces:

  • string Will convert string to []byte and write to ResponseWriter

  • []byte Write to ResponseWriter

  • error If error is not nil, Write header 500 and the content is error.Error()

  • AbortError if AbortError, Write header AbortError.Code and the content is AbortError.Error()

And if you have an anonymous tango.JSON or tango.XML, the return value could be:

  • error If it's Json, will reproduce {"err": err.Error()}

  • map If it's Json, will reproduce json

  • slice

  • structs will reproduce json

For example, we will write a json response.

type Action struct {

var i int
func (Action) Get() interface{} {
   if i == 0 {
       i = i + 1
       return map[string]interface{}{"i":i}
   return errors.New("could not visit")

func main() {
    t := tango.Classic()
    t.Any("/", new(Action))