Correct use of splice() in Javascript

1.splice() syntax

arrayObject.splice(index,deleteCount,item1,.....,itemX)

• ##index : Specify the starting position of modification (counting from 0)

• deleteCount: Indicates the number of array elements to be deleted.

• item1,...,itemX: The elements to be added to the array start from the index position. If not specified, splice() will only remove array elements.

Return value: an array composed of the deleted elements. If only one element was removed, an array containing only one element is returned. If no elements were removed, an empty array is returned.

2. Usage example

Deleting array elements:

     <script>
          arr1=[9,2,6,4,5];
          res1=arr1.splice(2);
          console.log(res1);//[6, 4, 5]被删除的元素
          console.log(arr1);//[9,2]剩余元素

          arr2=[9,2,6,4,5];
          res2=arr2.splice(2,2);
          console.log(res2);//[6, 4]被删除的元素
          console.log(arr2);//[9,2,5]剩余元素
    </script>

Adding new array elements:

    <script>
          arr3=[9,2,6,4,5];
          console.log(arr3);
          result=arr3.splice(1,0,99,10);
        //   console.log(result);空数组
          console.log(arr3);
          result=arr3.splice(2,0,...[111]);
          console.log(arr3);
    </script>

Deleting array elements:

    <script>
          arr4=[1,2,3,4,5];
          res=arr4.splice(1,3,...[88,99,44]);
          console.log(arr4);
    </script>

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