Structs as Classes

Part of the Object Oriented Programming section of Coddy's GO journey — lesson 6 of 107.

Structs in Go serve the same purpose as classes in other languages. They bundle related data together into a single type.

Define a struct with multiple field types

type Car struct {
    Brand string
    Model string
    Year  int
    Price float64
}

Create an instance using field names

car := Car{
    Brand: "Toyota",
    Model: "Camry",
    Year:  2023,
    Price: 28000.50,
}

Access and modify fields

fmt.Println(car.Brand) // Toyota
fmt.Println(car.Year)  // 2023

car.Price = 27000.00   // Modify a field
fmt.Println(car.Price) // 27000

Structs can contain other structs

type Engine struct {
    Horsepower int
    FuelType   string
}

type Car struct {
    Brand  string
    Model  string
    Engine Engine
}

car := Car{
    Brand:  "Ford",
    Model:  "Mustang",
    Engine: Engine{Horsepower: 450, FuelType: "Gasoline"},
}
fmt.Println(car.Engine.Horsepower) // 450

Structs group related fields together. You access fields with the dot operator, and you can nest structs inside other structs to build complex data models.

Challenge

Medium

Define a Profile struct with the following fields:

Name — string
Email — string
Age — int
Role — string

Cheat sheet

Structs in Go bundle related data together into a single type, similar to classes in other languages.

Define a struct with multiple field types:

type Car struct {
    Brand string
    Model string
    Year  int
    Price float64
}

Create an instance using field names:

car := Car{
    Brand: "Toyota",
    Model: "Camry",
    Year:  2023,
    Price: 28000.50,
}

Access and modify fields using the dot operator:

fmt.Println(car.Brand) // Toyota
car.Price = 27000.00   // Modify a field

Structs can contain other structs (nested structs):

type Engine struct {
    Horsepower int
    FuelType   string
}

type Car struct {
    Brand  string
    Model  string
    Engine Engine
}

car := Car{
    Brand:  "Ford",
    Model:  "Mustang",
    Engine: Engine{Horsepower: 450, FuelType: "Gasoline"},
}
fmt.Println(car.Engine.Horsepower) // 450

Try it yourself

package main

import "fmt"

func main() {
    var name, email, role string
    var age int
    fmt.Scan(&name, &email, &age, &role)

    p := Profile{
        Name:  name,
        Email: email,
        Age:   age,
        Role:  role,
    }

    fmt.Printf("Name: %s\n", p.Name)
    fmt.Printf("Email: %s\n", p.Email)
    fmt.Printf("Age: %d\n", p.Age)
    fmt.Printf("Role: %s\n", p.Role)
}