The break
command in the switch-case
construct is optional. In the absence of break
,
after the planned case
is executed, all
case
below it will also be executed.
Let's look at an example:
let num = 1; // let be here the number 1
switch (num) {
case 1:
console.log(1); // it will work
case 2:
console.log(2); // and this too
case 3:
console.log(3); // and this too
}
Let's change the value of the variable:
let num = 2; // let be here the number 2
switch (num) {
case 1:
console.log(1);
case 2:
console.log(2); // it will work
case 3:
console.log(3); // and this too
}
Let's change the value of the variable:
let num = 3; // let be here the number 3
switch (num) {
case 1:
console.log(1);
case 2:
console.log(2);
case 3:
console.log(3); // it will work
}
Sometimes this feature is used when solving problems. See an example:
let num = 1;
let res;
switch (num) {
case 1:
case 2:
res = 'a';
break;
case 3:
res = 'b';
break;
}
console.log(res);
It's more obvious, however, to solve
such a problem through if
:
let num = 1;
let res;
if (num == 1 || num == 2) {
res = 'a';
}
if (num == 3) {
res = 'b';
}
console.log(res);