alternative for foreach and use regular for loop

Question

This doesnt really work in IE

[].forEach.call(document.querySelectorAll('.some-class-selector'), function(arg) {

   callSomeFucntion(arg)

});

because forEach doesn't work on IE. if I want to do this using for loop, how would I do this?

Possible duplicate of [Loop through an array in JavaScript](https://stackoverflow.com/questions/3010840/loop-through-an-array-in-javascript) — Phiter, Apr 16 '18 at 19:42
search [here](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach) for "polyfill" — caramba, Apr 16 '18 at 19:44
Possible duplicate of [For-each over an array in JavaScript?](https://stackoverflow.com/questions/9329446/for-each-over-an-array-in-javascript) — caramba, Apr 16 '18 at 19:45
[`forEach` has been supported since IE9](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach#Browser_compatibility). What version of IE are you using? — zero298, Apr 16 '18 at 19:51
May I suggest you look into transpiling, working around old browser technology is one way to make me puke.!!. Get into modern ESNext features and use `for of`.. — Keith, Apr 16 '18 at 19:58

score 0 · Answer 1 · answered Apr 16 '18 at 19:45

0

Need to add this for run forEach in IE

<meta http-equiv="X-UA-Compatible" content="IE=9; IE=8; IE=7" />

answered Apr 16 '18 at 19:45

Mohammad Ali Rony

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score -1 · Answer 2 · edited Apr 16 '18 at 19:53

What version of IE are you using? The Microsoft docs page for forEach lists the version that don't support it - mainly IE 6,7 and 8 or quirks mode (https://learn.microsoft.com/en-us/scripting/javascript/reference/foreach-method-array-javascript)

You can also use a polyfill if your browser won't support it MDN forEach:

forEach() was added to the ECMA-262 standard in the 5th edition; as such it may not be present in other implementations of the standard. You can work around this by inserting the following code at the beginning of your scripts, allowing use of forEach() in implementations that don't natively support it. This algorithm is exactly the one specified in ECMA-262, 5th edition, assuming Object and TypeError have their original values and that callback.call() evaluates to the original value of Function.prototype.call().

// Production steps of ECMA-262, Edition 5, 15.4.4.18
// Reference: http://es5.github.io/#x15.4.4.18
if (!Array.prototype.forEach) {

Array.prototype.forEach = function(callback/*, thisArg*/) {

var T, k;

if (this == null) {
  throw new TypeError('this is null or not defined');
}

// 1. Let O be the result of calling toObject() passing the
// |this| value as the argument.
var O = Object(this);

// 2. Let lenValue be the result of calling the Get() internal
// method of O with the argument "length".
// 3. Let len be toUint32(lenValue).
var len = O.length >>> 0;

// 4. If isCallable(callback) is false, throw a TypeError exception. 
// See: http://es5.github.com/#x9.11
if (typeof callback !== 'function') {
  throw new TypeError(callback + ' is not a function');
}

// 5. If thisArg was supplied, let T be thisArg; else let
// T be undefined.
if (arguments.length > 1) {
  T = arguments[1];
}

// 6. Let k be 0.
k = 0;

// 7. Repeat while k < len.
while (k < len) {

  var kValue;

  // a. Let Pk be ToString(k).
  //    This is implicit for LHS operands of the in operator.
  // b. Let kPresent be the result of calling the HasProperty
  //    internal method of O with argument Pk.
  //    This step can be combined with c.
  // c. If kPresent is true, then
  if (k in O) {

    // i. Let kValue be the result of calling the Get internal
    // method of O with argument Pk.
    kValue = O[k];

    // ii. Call the Call internal method of callback with T as
    // the this value and argument list containing kValue, k, and O.
    callback.call(T, kValue, k, O);
  }
  // d. Increase k by 1.
  k++;
}
// 8. return undefined.
};
}

alternative for foreach and use regular for loop

2 Answers2