javascript code to insert an array into another array_javascript tips

Insert array arr2 into the index position of array arr1:

Copy code The code is as follows:

var arr1 = ['a', 'b', 'c'];
var arr2 = ['1', '2', '3'];
var index = 1;
arr2.unshift (index, 0);Array.prototype.splice.apply(arr1, arr2);
console.log(arr1);

Display results:

Copy code The code is as follows:

["a", "1", "2", "3", "b", "c"]