Switch Statements

2:25 with Jay McGavren

To choose between several options with "if" / "else" statements, you'd have to nest them several deep, which is hard to read. So like most programming languages, Go offers a "switch" statement. You specify the expression you want to switch on, "case" statements with possible values for that expression, and one or more lines of code that should run in each case.

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To choose between several options with if / else statements, you'd have to nest them several deep, which is hard to read
So like most programming languages, Go offers a switch statement.
You specify the expression you want to switch on, case statements with possible values for that expression, and one or more lines of code that should run in each case.
You can add a default case at the end, that will run if none of the other cases match.

package main

import (
    "fmt"
)

func main() {
    fmt.Print("You win: ")
    doorNumber := 2
    switch doorNumber {
    case 1:
        fmt.Println("a new car!") // not printed
    case 2:
        fmt.Println("a llama!") // printed
    default:
        fmt.Println("a goat!") // not printed
    }
}

To choose between several different options, using if and 0:00 else states, you'd have to nest some several deep, which can be hard to read. 0:03 So like most programming languages, Go offers a switch statement. 0:07 You specify the expression you wanna switch on, case statements with 0:11 possible values for that expression, and then code that should run for each case. 0:14 You can also add the default case at the end, 0:20 that will run if none of the other cases match. 0:22 So up here, we've initialized the doorNumber variable with the value 2, 0:25 the integer 2. 0:30 And we're going to switch on the value that's in doorNumber. 0:32 So we've got case statements here, for possible values of doorNumber. 0:35 If doorNumber was set to 1, we would print the string, a new car! 0:38 But up here, it's actually set to 2, so 0:44 it's going to match this case here, case number 2. 0:47 And it means that his code here will run, it will print the string, a llama! 0:51 So if we try running this down here, we'll see, You win a llama! 0:57 Let's try going up here into the code and setting it to 1, so 1:01 that we can look at the other case. 1:04 Try running this again. 1:07 This time, you can see we won a new car. 1:08 And if we set it to some completely different value, 1:10 let's say we pick door number 99. 1:14 In that case none of the cases here will match, and 1:16 therefore the default case will run instead. 1:20 And it will print, You win a goat! 1:24 Let's change this back to doorNumber 1, up here. 1:27 In some languages, the case after the selected case will also run, 1:31 unless you insert a break statement at the end of the case. 1:34 In Go, only the selected case runs by default. 1:37 So, if we select doorNumber 1, only doorNumber 1 runs. 1:40 But you can run the next case as well, 1:43 if you explicitly include the fallthrough keyword. 1:46 So lets type fallthrough here, and try re-running it. 1:51 And now, we win both a new car and a llama. 1:55 That ends our tour of control structures in Go. 1:58 Go's a very simple language, so 2:01 you've actually learned a substantial part of its syntax already. 2:03 The next stage is going to be a bit longer than this one. 2:08 We're going to look at the different ways Go can store data, and 2:10 there are a lot of them. 2:13 We'll learn about slices, maps, structs and more. 2:15 Learning them will take a bit of work, but 2:18 when you're done, you'll have a variety of ways to simplify your programs. 2:19 See in the next stage. 2:23

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Go Language Overview

Switch Statements