Mestika
10/11/2019 - 5:30 AM

JavaScript: Move an array element from one position to another

https://www.w3resource.com/javascript-exercises/javascript-array-exercise-38.php https://codepen.io/w3resource/pen/dVRLqN

Test Data: console.log(move([10, 20, 30, 40, 50], 0, 2)); [20, 30, 10, 40, 50] console.log(move([10, 20, 30, 40, 50], -1, -2));

script.js
content_copyfile_download
function move(arr, old_index, new_index) {
    while (old_index < 0) {
        old_index += arr.length;
    }
    while (new_index < 0) {
        new_index += arr.length;
    }
    if (new_index >= arr.length) {
        var k = new_index - arr.length;
        while ((k--) + 1) {
            arr.push(undefined);
        }
    }
     arr.splice(new_index, 0, arr.splice(old_index, 1)[0]);  
   return arr;
}

console.log(move([10, 20, 30, 40, 50], 0, 2));

console.log(move([10, 20, 30, 40, 50], -1, -2));

/**
 * [20,30,10,40,50]
 * [10,20,30,50,40]
 */