Overview

Enum in Golang can be created by using IOTA. Please refer to this post to learn more about IOTA

IOTA in Go (Golang)

In this post, we will see how to convert an IOTA or enum to a string value. By default when you will print an IOTA or enum value it will print the integer part of it. See this example. Later we will see an example of we can define a custom toString method to print the string value of IOTA or enum

Example

package main

import "fmt"

type Size uint8

const (
	small Size = iota
	medium
	large
	extraLarge
)

func main() {
	fmt.Println(small)
	fmt.Println(medium)
	fmt.Println(large)
	fmt.Println(extraLarge)
}

Output

0
1
2
3

We can also define a method toString on Size type to print the exact value of enum . See below program

package main
import "fmt"
type Size int
const (
    small = Size(iota)
    medium
    large
    extraLarge
)
func main() {
    var m Size = 1
    m.toString()
}
func (s Size) toString() {
    switch s {
    case small:
        fmt.Println("Small")
    case medium:
        fmt.Println("Medium")
    case large:
        fmt.Println("Large")
    case extraLarge:
        fmt.Println("Extra Large")
    default:
        fmt.Println("Invalid Size entry")
    }
}

Output

medium

We will now define a toString method for the Size type. It can be used to the print the string value of the constant of Size type.