如何创建通用函数以解组所有类型？

I have a function below, and I would like to make it generic:

func genericUnmarshalForType1(file string) Type1 {

  raw, err := ioutil.ReadFile(file)

  if err != nil {
      fmt.Println(err.Error())
      os.Exit(1)
  }

  var type1 Type1

  json.Unmarshal(raw, &type1)
}

I would like to create a function that accepts Type1 or Type2 without the need to create a function per type. How can I do this?

Do it the same way json.Unmarshal does it:

func genericUnmarshal(file string, v interface{}) {
    // File emulation.
    raw := []byte(`{"a":42,"b":"foo"}`)
    json.Unmarshal(raw, v)
}

Playground: http://play.golang.org/p/iO-cbK50BE.

You can make this function better by actually returning any errors encountered.

Go doesn't support generics, but you can write something like this:

func genericUnmarshalForType1(file string) interface{} {

    raw, err := ioutil.ReadFile(file)

    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }

    var x interface{}
    if err = json.NewDecoder(raw).Decode(x); err != nil {
        return nil
    }

    return x
}

func main() {
    x := genericUnmarshalForType1("filename.json");

    var t1 Type1
    var t2 Type2

    switch t := x.(type) {
    case Type1:
        t1 = t
    case Type2:
        t2 = t
    }
}

Also I recommend you to read http://attilaolah.eu/2013/11/29/json-decoding-in-go/ about Unmarshal using and data types.