I have below snippet

data.forEach(function (row) {
var dataRow = [];

columns.forEach(function (column) {

dataRow.push(row[column].toString());
})

which is giving me error data.forEach(function (row) { .What should be alternate to this? How to resolve it?

I have below snippet

data.forEach(function (row) {
var dataRow = [];

columns.forEach(function (column) {

dataRow.push(row[column].toString());
})

which is giving me error data.forEach(function (row) { .What should be alternate to this? How to resolve it?

• javascript
• jquery
• arrays
• internet-explorer

• 1 Else you can also use the polyfil developer.mozilla/en-US/docs/Web/JavaScript/Reference/… – brk Commented Sep 11, 2018 at 4:56
• 1 @brk this polyfill is for Array#forEach The one the dupe target was talking about is NodeList#forEach. Also, RAM can you confirm it was indeed this NodeList#forEach that you were trying to use. – Kaiido Commented Sep 11, 2018 at 5:04
• nodelist#forEach polyfill - I doubt the OP was talking about NodeList though – Jaromanda X Commented Sep 11, 2018 at 5:14
• Yes, it sounds more like data is not what it should be. I reopen (save-link-to-prev-dupe-target). But note that as it stands this question should still be closed, because it lacks some information and debugging steps you should have taken on your side (like what is data before you call its non-existent forEach method?) – Kaiido Commented Sep 11, 2018 at 5:20
• You can't loop through forEach when data is an object. It should run on array. In order to loop through the object, you should try: for (var key in data) { if (data.hasOwnProperty(key)) { console.log(key + " -> " + data[key]); // Here you will get key and value } } – Ankit Commented Sep 11, 2018 at 5:50

2 Answers 2

For anyone using document.querySelectorAll('..').forEach() and having this issue in IE 11 saying "forEach is not a function", I found a hack on reddit which worked nicely:

if (typeof NodeList.prototype.forEach !== 'function')  {
    NodeList.prototype.forEach = Array.prototype.forEach;
}

This works perfectly and is 3 lines of code instead of a polyfill.

@JoeTaras hinted at this in his answer (yes IE does have Array.forEach since IE9), but I still think my answer adds value and will help other users.

IE11 knows forEach statement (is IE pliant from IE 9.0, see here), but if you want you can use instead of forEach you can use for statement, as follow:

I've edited my answer, add a check on data object if is an array

if (data != null && Array.isArray(data)) {
    var dataRow = [];
    for (var i = 0; i < data.length; i++) {
        var row = data[i];
        for (var j = 0; j < columns.length; i++) {
            var column = columns[i];

            dataRow.push(row[column].toString());
        }
    }
}