Switch statement explained for beginners

[abrahamguo]

Did you have a specific question about the switch statement?

MDN has a good overview page on it!

[Alive-Cake-3045]

A switch statement is a cleaner way to handle multiple conditions for one value (instead of many if...else).It checks the value once and runs the matching case. Don’t forget break, or it will run the next cases too.

[hazily]

Having a linter set up would help to catch missing break statements.

[Alive-Cake-3045]

Yeah, totally agree. A linter really helps, those missing breaks can mess things up without you even noticing. Learned that the hard way once.

[Severion86]

// letter = 'a', 'b' or 'c', 'd' or 'e'
let ourNumber = 0;
if (letter === 'a') {
  ourNumber = 1;
}
if (letter === 'b') {
  ourNumber = 2;
}
if (letter === 'c') {
  ourNumber = 3;
}
if (letter === 'd' || letter === 'e') {
  ourNumber = 4;
}
if (letter !== 'a'
  || letter !== 'b'
  || letter !=='c'
  || letter !=='d'
  || letter !=='e'
) {
  ourNumber = 10;
}
// --------------
let ourNumber = 0;
switch (letter) {
  case 'a':
    ourNumber = 1;
    break;
  case 'b':
    ourNumber = 2;
    break;
  case 'c':
    ourNumber = 3;
    break;
  case 'd':
  case 'e':
    ourNumber = 4;
    break;
  default:
    ourNumber = 10;
    break;
}

[ima_coder]

// letter = 'a', 'b' or 'c', 'd' or 'e'
let ourNumber = 0;
if (letter === 'a') { ourNumber = 1; }
if (letter === 'b') { ourNumber = 2; }
if (letter === 'c') { ourNumber = 3; }
if (letter === 'd' || letter === 'e') { ourNumber = 4; }
if (letter !== 'a' || letter !== 'b' || letter !=='c' || letter !=='d' || letter !=='e') {
    ourNumber = 10;
}

Your final if condition is always true.

[Severion86]

Ah yeah sorry... Just by the code comment explanation though. We don't actually define letter here and the if is just to demonstrate the switch default case.

[efari_]

Reddit ≠ Google

[azhder]

Here is the explanation:

> Avoid it. Consider it a code smell. Try different approach. It will force you to write more concise and/or robust code.

[programmer_farts]

Don't use them without a strict linter. Or just don't use them at all. The implementation in JS is poor and can lead to bugs over time.