How to break 2 loops in javascript?

Question

I tried this:

for(i=0;i<5;i++)
{
    for(j=i+1;j<5;j++)
    {
        break(2);
    }
    alert(1)
};

only to get:

SyntaxError: missing ; before statement

Answer 1

break doesn't take parameters. There are two workarounds:

1. Wrap them in a function and call return

2. Set a flag in the inner loop and break again right after the loop if the flag is set.

Answer 2

You should be able to break to a label, like so:

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

Answer 3

Unfortunately you'll have to set a flag or use labels (think old school goto statements)

var breakout = false;

for(i=0;i<5;i++)
{
for(j=i+1;j<5;j++)
{
    breakout = true;
    break;
}
if (breakout) break;
alert(1)
};

The label approach looks like

end_loops:
for(i=0;i<5;i++)
{
for(j=i+1;j<5;j++)
{
    break end_loops;
}
alert(1)
};

edit: label incorrectly placed. also see http://www.devguru.com/Technologies/ecmascript/quickref/break.html and http://www.daaq.net/old/javascript/index.php?page=js+exiting+loops&parent=js+statements

Answer 4

Break 1st loop:

for(i=0;i<5;i++)
{
  for(j=i+1;j<5;j++)
  {
    //do something

    break;
  }
  alert(1);
};

Break both loops:

for(i=0;i<5;i++)
{
  var breakagain = false;
  for(j=i+1;j<5;j++)
  {
    //do something

    breakagain = true;
    break;
  }
  alert(1);
  if(breakagain)
    break;
};

Answer 5

You need to name your outer loop and break that loop, rather than your inner loop - like this.

outer_loop: 
for(i=0;i<5;i++) {
    for(j=i+1;j<5;j++) {
     break outer_loop;
    }
    alert(1);
}

Answer 6

See Aaron's. Otherwise: j=5;i=5 instead of break.

Answer 7

loop1:
    for (var i in set1) {
loop2:
        for (var j in set2) {
loop3:
            for (var k in set3) {
                break loop2;  // breaks out of loop3 and loop2
            }
        }
    }

code copied from http://stackoverflow.com/questions/183161/best-way-to-break-from-nested-loops-in-javascript/183197#183197

Please search before posting a question. The link was the FIRST related question I saw on the left side of this page!

Answer 8

function myFunction(){
  for(var i = 0;i < n;i++){
    for(var m = 0;m < n;m++){
      if(/*break condition*/){
        goto out;
      }
    }
  }
out:
 //your out of the loop;
}

Answer 9

Use function for multilevel loops - this is good way:

function find_dup () {
    for (;;) {
        for(;;) {
            if (done) return;
        }
    }
}