从结构图调用结构

Question

Hi I am trying something like the following example.

My background as a PHP Developer (I know!) is giving me a hard time on this. I've read the Laws of reflection and other sources, but this is over my head. The approach i am using is probably wrong... and hope someone can point me in the right direction.

The use of this in a concrete way is that the version 01 or 02 or 03 is comming from an external Parameter, based on that, I need to get the appropriate struct and populate it with database values.

package V01
type Struct1 struct{
    Field1 string
    Field2 string
}

type Struct2 struct{
    Field1 string
    Field2 string
}

---

package V02
type Struct1 struct{
    Field1 string
    Field2 string
    ExtraField1 string
}

type Struct2 struct{
    Field1 string
    Field2 string
    ExtraField2 string
    ExtraField3 string
}

---

var VStructs = map[string]map[string]interface{}{
    "01": map[string]interface{}{
        "Struct1": V01.Struct1{},
        "Struct2": V01.Struct2{},
    },
    "02": map[string]interface{}{
        "Struct1": V02.Struct1{},
        "Struct2": V02.Struct2{},
    }, 
    "03" : map[string]interface{}{
        "Struct1": V01.Struct1{},
        "Struct2": V02.Struct2{},
    }, 
}

---

 // I get the struct fieldnames and so on.
 fmt.Printf("%+v
", VStructs["01"]["Struct1"] ) 

 // I cannot access any of the fields though because it is an interface
 fmt.Println( VStructs["01"]["Struct1"].Field1 ) // PANIC! 

 // Type Switching is not working either since the version can be variable.
 s := VStructs["01"]["Struct1"].Field1 
 switch x := s.(type) {
 case reflect.Struct: // PANIC! reflect.Struct (type reflect.Kind) is not a type
    fmt.Println("I am an struct")
 default:
    fmt.Println("I am an no struct")
 }

---

So maybe can show me an appropriate way of doing this. Or maybe an wrapper function to return the right struct... no clue at this point.

Hope it is clear, and will elaborate more if asked to.

Answer 1

Okay, since the question was probably in conflict with the way golang is used to work.

I have written an package to serve my needs :

Based on the selected version (In the URL or the Header, whatever you like) we retrieve an map of structs. We now can select the actual struct we need, set some values and finally send it back to the screen OR send it over to the DB (In my case gorp).

The Package can be found here https://github.com/donseba/contractor/