结构

import "reflect"

type S struct {
    A int
    b string
}

func (s *S) String() { return s.b }

s := &S{
    A: 5,
    b: "example",
}

indirect := reflect.ValueOf(s) // effectively a pointer to an S
value := indirect.Elem()       // this is addressable, since we've derefed a pointer

value.FieldByName("A").Interface() // 5
value.Field(2).Interface()         // "example"

value.NumMethod()    // 0, since String takes a pointer receiver
indirect.NumMethod() // 1

indirect.Method(0).Call([]reflect.Value{})              // "example"
indirect.MethodByName("String").Call([]reflect.Value{}) // "example"