Delete v/s Splice for JavaScript Array

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Use "splice" instead of "delete" to delete an item from an array because "Delete" replaces the item with undefined instead of the removing it from the array.


var fruits = ["apple", "banana", "grapes"];
fruits.length; // return 3
delete fruits[1]; // return true
fruits.length; // return 3


Instead

var fruits = ["apple", "banana", "grapes"];
fruits.length; // return 3
fruits.splice(2,1) ;
fruits.length; // return 2

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