JavaScript Array forEach

JavaScript Array forEach() is used to execute a given function for each element in the Array.

In this tutorial, we shall learn the syntax and usage of forEach with Examples.

Syntax

The syntax of forEach() function is

arr.forEach(function callbackFun(currentValue[, index[, array]]) {
    //set of statements
}[, thisArg]);

where

Keyword/Variable/ Parameter Mandatory/ Optional Description
arr Mandatory The array containing elements.
callbackFun Optional Function which has to be applied for each element of array
currentValue Mandatory The current element’s value for which callback function is being applied.
index Optional Index of the current element.
array Optional Array, on which forEach is being applied.
thisArg Optional thisArg is provided to forEach. Used as this value in forEach. arr.forEach(callbackFun, thisArg);

Example

In the following example, we take an array, and iterate over the elements using forEach() method.

index.html

<!doctype html>
<html>
<body>
    <h1>JavaScript - forEach Example</h1>
    <p id="message"></p>
    
    <script>
        <!-- your JavaScript goes here -->
        var msg='';
        var names = ['Arjun', 'Akhil', 'Varma'];
        
        names.forEach(function printing(element, index, names){
            msg += index + ' : ' + element + '<br>';
        });
        
        document.getElementById("message").innerHTML = msg;
    </script>
    
</body>
</html>

Conclusion

In this JavaScript Tutorial, we have learnt to use Array.forEach() method to apply a function for each element of the array.