How do you loop through the fields in a Golang struct to get and set values in an extensible way?

Question

I have a struct Person.

type Person struct {
    Firstname string       
    Lastname  string       
    Years     uint8       
}

Then I have t

Answer 1

Here is the solution f2.Set(reflect.Value(f)) is the key here

package main

   import (
    "fmt"
    "reflect"
   )

   func main() {
    type T struct {
        A int
        B string
    }
    t := T{23, "skidoo"}
    t2:= T{}
    s := reflect.ValueOf(&t).Elem()
    s2 := reflect.ValueOf(&t2).Elem()
    typeOfT := s.Type()
    fmt.Println("t=",t)
    fmt.Println("t2=",t2)

    for i := 0; i < s.NumField(); i++ {
        f := s.Field(i)
        f2:= s2.Field(i)
        fmt.Printf("%d: %s %s = %v\n", i,
            typeOfT.Field(i).Name, f.Type(), f.Interface())
        fmt.Printf("%d: %s %s = %v\n", i,
            typeOfT.Field(i).Name, f2.Type(), f2.Interface())
        f2.Set(reflect.Value(f))
        fmt.Printf("%d: %s %s = %v\n", i,
            typeOfT.Field(i).Name, f2.Type(), f2.Interface())

    }
    fmt.Println("t=",t)
    fmt.Println("t2=",t2)
}

Output:

t= {23 skidoo}
t2= {0 }
0: A int = 23
0: A int = 0
0: A int = 23
1: B string = skidoo
1: B string = 
1: B string = skidoo
t= {23 skidoo}
t2= {23 skidoo}

http://play.golang.org/p/UKFMBxfbZD