Golang Reflection: Inspect a struct type definition to extract its properties without initialization

Question

If I have the following declaration

type Foo struct {
   bar string
}

Can I use reflection to inspect the properties on the declaration without initialising it?

keys := reflect.something(Foo)

for _, key := range keys {
    fmt.Println(key) // "bar"
}

score 2 · Accepted Answer · 2020-04-05 03:16:16Z

2

Use reflect.TypeOf to get the reflect.Type for Foo.

t := reflect.TypeOf(Foo{})

If you don't want to create a value of the type, then get the pointer type and "dereference" that type.

t := reflect.TypeOf((*Foo)(nil)).Elem()

The expression (*Foo)(nil) returns a nil pointer to the type. The Type.Elem method returns the pointed to type.

Iterate through the fields on the type. Type.NumField returns the number of fields on the type. Type.Field returns a StructField by field index.

for i := 0; i < t.NumField; i++ {
    fmt.Println(t.Field(i).Name)
}

answered Apr 5, 2020 at 3:11

user12258482

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