how does js delete the value of an array element, but still occupy the original position?
how does js delete the value of an array element, but still occupy the original position?
non-strict mode can use delete, or directly take the subscript and set the corresponding position value to null or undefined;
then this is not called deletion, it is called replacement. Replace the corresponding position with null or undefined or'
after deleting the value of the array element, its address reference still exists. It's just an empty character.
a = ['one',' two'];
delete a [0];
/ / a now is: [undefined, 'two'];
a.length = 10;
/ / a now the result is: [undefined, 'two', undefined x 8]
array remains the same.
it's not clear whether you're talking about occupying the original position, meaning that the position of the element is retained or the address of the array remains the same.
the previous answer is the first, but the real-world scenario may require the second.
suppose you want to delete the second element, "2"
let a = [1,2, 3]
a.splice(1,1)I hope it will help you.
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