how to break from a foreach loop

Question

I am trying to break from a foreach loop. I want to test conditions and break from the loop once the condition is met. The problem is it keeps looping through the json array, even on the false ones. I just want it to stop if the condition is met. I am aware that you cannot actually break from a foreach loop but what is a good alternative here? I am having trouble understanding where to put the break statements. Thank you very much.

 $.ajax({
        // Get the values of the cce json file
        url: 'file.json',
        success: function (data) {
            data.forEach(function(row) {                  
              if (row.ATTR == feature.properties.AATR) {
                 // code to execute here
                 // once the condition is met once, stop execution of foreach
               } else {
                // some other code to execute
               // keep going
               }

well forEach is the wrong loop if you want to break from it. You probably want to use every, some, or find depending on your goal. — epascarello, Aug 23 '19 at 20:15

score 1 · Answer 1 · answered Aug 23 '19 at 20:18

1

You can't break forEach loop. You need to use a different type of loop.

See the docs:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach

answered Aug 23 '19 at 20:18

Victor P

1,496
17
29

Wellington Lopes · Answer 2 · 2019-08-23T20:33:45.857

0

You should use a for loop. It is a function that simulate it.

for (var i in data) {
    if (condition_to_break) {
        break;
    }
}

.forEach is a function and doesn't do break.

edited Aug 23 '19 at 20:33

answered Aug 23 '19 at 20:17

Wellington Lopes

65
1
5

`for..in` does not the same as `forEach`. – Ivar Aug 23 '19 at 20:19
Yes, you just can't do it in a .forEach. It is not a loop :) – Wellington Lopes Aug 23 '19 at 20:20
My point is, is that a `for.in` loop is not a replacement for the `forEach`. `forEach` loops over all the elements while the `for..in` loops over the properties. – Ivar Aug 23 '19 at 20:22
That is true, that why you can't use 'break' command in that case. It is a function that uses a callback function in argument, even if you use 'return' it doesn't stop. – Wellington Lopes Aug 23 '19 at 20:25
Yes I'm aware but that is not what I'm talking about. – Ivar Aug 23 '19 at 20:27

how to break from a foreach loop

2 Answers2