JavaScript copy Array

Several methods of commonly used replicated arrays

Direct ARR1 = Arr2 This method copies a reference to the original array, and modifying the copied new array changes the contents of the original array.

var arr = [1, 2, 3, 6];var arr_ = Arr;console.log (arr_);//1,2,3,6arr_.splice (2, 0, 4, 5); Console.log (ARR_);//1,2,3,4,5,6;c Onsoe.log (arr);//1,2,3,4,5,6;

Because the copy is a reference to an array, the original array is changed, and the original array can be changed as well. Here's an example of Xiaoice

var array1 = new Array ("1", "2", "3"); var array2; Array2 = array1; array1.length = 0; alert (array2); Return to Empty

A good practice, in addition to using for To loop, you can also use the slice () method or the Concat () method to operate the array

var arr1 = [1, 2, 3];var arr2 = arr1.slice (0); Arr2.splice (3,0,4,5); Console.log (ARR2);//1,2,3,4,5console.log (arr1);// The

　　

var arr1 = [1, 2, 3];var arr2 = Arr1.concat ([]); Arr2.splice (3,0,4,5); Console.log (ARR2);//1,2,3,4,5console.log (arr1);// The

Because Slice and concat return a new array, these two methods can be used for replication

JavaScript copy Array