how to declare a 2d array in javascript code example

Example 1: js initialize 2d array

let data = [];
for (let row=0; row<rows; row++) {
    data.push(new Array(cols).fill('#'));
};

Example 2: creating a 2d array in js

var x = new Array(10);

for (var i = 0; i < x.length; i++) {
  x[i] = new Array(3);
}

console.log(x);

Example 3: how to create 2d array in javascript

// program to create a two dimensional array

function twoDimensionArray(a, b) {
    let arr = [];

    // creating two dimensional array
    for (let i = 0; i< a; i++) {
        for(let j = 0; j< b; j++) {
            arr[i] = [];
        }
    }

    // inserting elements to array
    for (let i = 0; i< a; i++) {
        for(let j = 0; j< b; j++) {
            arr[i][j] = j;
        }
    }
    return arr;
}

const x = 2;
const y = 3;

const result = twoDimensionArray(x, y);
console.log(result);

Example 4: creating 2d array in javascript

var [r, c] = [5, 5]; 
var m = Array(r).fill().map(()=>Array(c).fill(0));

Example 5: javascript two dimensional array

var grid = [];
iMax = 3;
jMax = 2;
count = 0;

    for (let i = 0; i < iMax; i++) {
      grid[i] = [];

      for (let j = 0; j < jMax; j++) {
        grid[i][j] = count;
        count++;
      }
    }

// grid = [
//   [ 0, 1 ]
//   [ 2, 3 ]
//   [ 4, 5 ]
// ];

console.log(grid[0][2]); // 4