CODEWITHSUNDEEP
javascriptfor-loopswitch-statementcontinue
BASILIO
BASILIO

Reputation: 887

Break for loop from inside of switch case in Javascript

What command I must use, to get out of the for loop, also from //code inside jump direct to //code after

//code before
for(var a in b)
    {
    switch(something)
        {
        case something:
            {
            //code inside
            break;
            }
        }
    }
//code after

Upvotes: 37

Views: 39036

Answers (9)

Muhammad Zeeshan
Muhammad Zeeshan

Reputation: 41

    const array = [1, 2, 3, 4, 5];

outerLoop: for (let i = 0; i < array.length; i++) {
  switch (array[i]) {
    case 1:
      console.log('Case 1');
      break; // This breaks out of the switch statement
    case 2:
      console.log('Case 2');
      break; // This breaks out of the switch statement
    case 3:
      console.log('Case 3');
      break outerLoop; // This breaks out of both the switch and the for loop
    default:
      console.log('Default case');
  }
}

console.log('Loop exited');

Upvotes: 0

Chubby Boy
Chubby Boy

Reputation: 31062

You can use label. Have a labeled statement and break to that label. outerLoop is the label I have used here.

//code before
outerLoop:
for (var a in b) {
    switch (something) {
        case 'case1':
            //code inside
            break outerLoop;
    }
}
//code after

Upvotes: 42

user3064538
user3064538

Reputation:

Replace your switch with a series of if statements.

for (const a of b) {
  if (something === someValue) {
    // code inside
    break; // break out of the for loop
  } else if (something === someOtherValue) {
    // etc.
  }
}

Upvotes: 2

lonesomeday
lonesomeday

Reputation: 237905

Unfortunately, Javascript doesn't have allow breaking through multiple levels. The easiest way to do this is to leverage the power of the return statement by creating an anonymous function:

//code before
(function () {
    for (var a in b) {
        switch (something) {
        case something:
            {
                //code inside
                return;
            }
        }
    }
}());
//code after

This works because return leaves the function and therefore implicitly leaves the loop, moving you straight to code after

As pointed out in the comments, my above answer is incorrect and it is possible to multi-level breaking, as in Chubby Boy's answer, which I have upvoted.

Whether this is wise is, from a seven-year-later perspective, somewhat questionable.

Upvotes: 18

Brad Christie
Brad Christie

Reputation: 101614

use another variable to flag when you need to exit:

var b = { firstName: 'Peter', lastName: 'Smith' };
var keepGoing = true;
for (var a in b) {
  switch (true) {
    case 1:
      keepGoing = false;
      break;
  }
  if (!keepGoing) break;
  console.log('switch end');
}
console.log('for end');

example

Upvotes: 28

gest
gest

Reputation: 49

for(var i=0; i<b.length; i++) {
   switch (something) {
       case 'something1':
           i=b.length;
   }
}

When the iteration variable i reaches the end of the loop, it breaks. But one can force the iteration variable to reach the end of the loop.

Upvotes: 1

Jeff
Jeff

Reputation: 111

it depends on what you want to accomplish... one thing I commonly do is something like this:

    //code before
for(var a in b)
{
    var breakFor = false;
    switch(something)
    {
        case something:
        {
            //code inside
            breakFor = true;
            break;
        }
    }
    if (breakFor)
        break;
}
//code after

Upvotes: 9

Skarlinski
Skarlinski

Reputation: 2479

You can tell which loop / switch to break.

function foo ()
{
    dance:
    for(var k = 0; k < 4; k++){
        for(var m = 0; m < 4; m++){
            if(m == 2){
                break dance;
            }
        }
    }
}

See this answer.

Upvotes: 4

Andrew_CS
Andrew_CS

Reputation: 2562

I always find using conditional statements one of the easiest ways to control the code flow, at least conceptually.

var done = false;
//code before for loop
for(var a in b){
    switch(switchParameter){
        case firstCase:
            //code inside
            done = true;
            break;
        }
    }
    if(done)
        break;
}
//code outside of for loop

Upvotes: 0

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