JavaScript Array forEach() Method Last Updated : 02 Sep, 2024 Comments Improve Suggest changes Like Article Like Report The JavaScript Array forEach() method is a built-in function that executes a provided function once for each array element. It does not return a new array and does not modify the original array. It's commonly used for iteration and performing actions on each array element.Syntaxarray.forEach(callback(element, index, arr), thisValue);ParametersThis method accept five parameters as mentioned above and described below:ParameterDescriptioncallbackIt is a callback function executes on each array element.elementThe current element being processed in the array.index (Optional)The index of current element. The array indexing starts from 0.array (Optional)The array on which forEach() is called.thisArg (Optional)Value to use as this when executing the callback function.Return valueIt does not return a new array. It returns undefined. This method may or may not change the original array provided as it depends upon the functionality of the argument function.Example 1: Basic iteration to print array elements on console. JavaScript const arr = [1, 2, 3, 4, 5]; arr.forEach((item) => { console.log(item); }); Output1 2 3 4 5 Example 2: Copy every element from one array to another array using Array.forEach() method. JavaScript // JavaScript Array forEach() Method // Original array const items = [12, 24, 36]; const copy = []; items.forEach(function (item) { copy.push(item); }); console.log(copy); Output[ 12, 24, 36 ] Example 3: Calculates the square of every element of the array using forEach() method. JavaScript // JavaScript Array forEach() Method // Original array const items = [1, 29, 47]; const squareOfItems = []; items.forEach(function (item) { squareOfItems.push(item * item); }); console.log(squareOfItems); Output[ 1, 841, 2209 ] Limitations of forEach() MethodNo Break or Continue: Unlike for loops, you cannot break the forEach() loop or use continue to skip to the next iteration. It will always iterate over all elements.No Return Value: The forEach() loop does not return a new array, it returns undefined.Asynchronous Issues: The forEach() loop does not handle asynchronous operations well. If you need to perform asynchronous operations, consider using for...of with async/await or Promise.all.Supported BrowsersGoogle ChromeEdge FirefoxOperaSafari Comment More infoAdvertise with us Next Article JavaScript Array forEach() Method H HGaur Follow Improve Article Tags : Misc JavaScript Web Technologies javascript-array JavaScript-Methods +1 More Practice Tags : Misc Similar Reads JavaScript Array() Constructor The Array() constructor is used to create Array objects and the array constructor can be called with or without a new keyword, both can create a new Array.Syntax:new Array(Value1, Value2, ...);new Array(ArrayLength);Array(Value1, Value2, ...);Array(ArrayLength);Parameters: ValueN: An array initializ 2 min read JavaScript Array constructor Property The JavaScript Array constructor property is used to return the constructor function for an array object. It only returns the reference of the function and does not return the name of the function. 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