Switches in JS

Switch = can be an efficient replacement to many else if statements

Normal code:

let day = "pizza";
 
if(day == 1){
	console.log(`it's monday`);
}
else if(day == 2){
	console.log(`it's tuesday`)
}
else if(day == 3){
	console.log(`it's wednesday`)
}
else if(day == 4){
	console.log(`it's thursday`)
}
else if(day == 5){
	console.log(`it's friday`)
}
else if(day == 6){
	console.log(`it's saturday`)
}
else if(day == 7){
	console.log(`it's sunday`)
}

Code by using switch:

let day = 1;
 
switch(day){
	case 1: 
		console.log(`it's monday`);
		break;
	case 2:
		console.log(`it's tuesday`);
		break;
	case 3:
		console.log(`it's wednesday`);
		break;
	case 4:
		console.log(`it's thursday`);
		break;
	case 5:
		console.log(`it's friday`);
		break;
	case 6:
		console.log(`it's saturday`);
		break;
	case 7:
		console.log(`it's sunday`);
		break;
	default:
		console.log(`${day} is not a day`)
}

brake here is to stop the code. let the code not execute the next code.

Another more complicate example:

let testScore = 92;
let letterGrade;
 
switch(true){
	case testScore >= 90;
		letterGrade = "A";
		break;
	case testScore >= 80
		letterGrade = "B";
		break;
	case testScore >= 70
		letterGrade = "C";
		break;
	case testScore >= 60
		letterGrade = "D";
		break;
	default:
		letterGrade = "F";
}
 
console.log(letterGrade);