switches


switch =


Statement(dichiarazione) that examines a value for a match against many case clauses.
More efficient that many "else if" statement, as show in the first example below


first example (not best choice)


let grade = "A"


if(grade == "A"){
console.log("You did great!")
}


else if(grade == "B"){
console.log("You did good!")
}

else if(grade == "C"){
console.log("You did ok!")
}

else if(grade == "D"){
console.log("You passed...barely!")
}

else if(grade == "F"){
console.log("You failed!")
}

else {
console.log("is not a letter grade!!")
}

console.log(age)

result: You did great!

good practice


let grade = "A"


switch(grade){

case "A":
console.log("You did great!")
break;

case "B":
console.log("You did good!")
break;

case "C":
console.log("You did ok!")
break;

case "D":
console.log("You passed...barely!")
break;

case "F":
console.log("You failed!")
break;

default:
console.log(grade, "is not a letter grade!")
// if is not "A", "B", "C", "D", "F", is "is not a ..."
}

result: You did great!

Or, different example with Numbers


let grade = 65

switch(true){

case grade >= 90:
console.log("You did great!")
break;

case grade >= 80:
console.log("You did good!")
break;

case grade >= 70:
console.log("You did ok!")
break;

case grade >= 60:
console.log("You passed...barely!")
break;

case grade > 60:
console.log("You failed!")
break;

default:
console.log(grade, "is not a letter grade!")
}

result: You passed...barely!