How to usea Loop in Javascript

In this approach, we are using nested loops to iterate over the rows and columns of the 2D array and initialize each element to a specific value as null or undefined.

Example: In this example, the Empty2DArray function generates a 2D array with the specified number of rows (3) and columns (4) filled with null values. The arr1 is the resulting array.

Javascript
function Empty2DArray(rows, cols) {
    const array = [];
    for (let i = 0; i < rows; i++) {
        array[i] = [];
        for (let j = 0; j < cols; j++) {
            array[i][j] = null;
        }
    }
    return array;
}

const arr1 = Empty2DArray(3, 4);
console.log(arr1);

Output
[
  [ null, null, null, null ],
  [ null, null, null, null ],
  [ null, null, null, null ]
]

How to Declare Two Dimensional Empty Array in JavaScript ?

In this article, we are going to learn about Declare two-dimensional empty array by using JavaScript. A two-dimensional array is also known as a 2D array. It is a data structure in JavaScript that can hold values in rows and columns form. It is an array of arrays. Each element in a 2D array is accessible using two indices, and it is represented as an array[rowIndex][columnIndex].

There are several methods that can be used to add elements to Declare an empty two-dimensional array in JavaScript, which are listed below:

Table of Content

  • Using a Loop
  • Using the Array() Constructor

We will explore all the above methods along with their basic implementation with the help of examples.

Similar Reads

Approach 1: Using a Loop

...

Approach 2: Using the Array() Constructor

In this approach, we are using nested loops to iterate over the rows and columns of the 2D array and initialize each element to a specific value as null or undefined....

Approach 3: Using Array.from() with a Mapping Function

JavaScript provides the Array() constructor, which allows us to create an array of a specific length. We can use this constructor to create a 2D array by initializing each element as an empty array....

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