I have an array like the one below.
let array = ["Sandy", 5, 2, 7]
I want to push a number of blank elements at the end of the array based on a variable ("x"). If x = 3, it would add three elements to the end of the array:
let array = ["Sandy", 5, 2, 7, , , ]
I know the push method allows you to add specific elements to the end of an array. How would I achieve this? Hope this question is clear
You could simply iterate the desired number of times and push undefined
:
function padArray(arr, num) { for (var i=0; i < num; ++i) { arr.push(undefined); } } var array = ["Sandy", 5, 2, 7]; console.log(array); padArray(array, 3); console.log(array);
take a for loop it's your answer, example:
var array=[your array]
for(x=0;x<length of your variable;x++){
array.push(your values to push)
}
var a = [1,2,3]
a = [ 1, 2, 3 ]
var c = Array(...a,...Array(3).fill(null))
c = [ 1, 2, 3, null, null, null ]
change 3 to any number you want
If you want to be fancy one liner to achieve it could look like:
let array = ["Sandy", 5, 2, 7] console.log([...array, ...(new Array(3))])
Are tree dots looks strange? If yes - then please feel free to read about https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment
.concat()
would do the job
let array = ["Sandy", 5, 2, 7] let x = 3; array = array.concat(Array(x)); console.log(array);
var arr = ["Sandy", 5, 2, 7];
var x = 3;
for(var i = 0 ; i < x ; i++){
arr.push("");
}
console.log(arr);
and result
["Sandy", 5, 2, 7, "", "", ""]
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