Perform unshift method on a copy of array

Question

I want to unshift on a copy of the array, but the original array modifies too. Why is that?

 var array1 = [1, 2, 3] var array2 = array1 array2.unshift(4, 5) console.log(array1) console.log(array2) 

Answer 1

Try using Array.from()

 var array1 = [1, 2, 3] var array2 = Array.from(array1) array2.unshift(4, 5) console.log(array1) console.log(array2) 

Answer 2

Use spread operator ( ... ) to make second array. It will make a new array with new reference. And then perform your task.

 var array1 = [1, 2, 3]; var array2 = [...array1]; array2.unshift(4, 5); console.log(array1); console.log(array2);