There is no need to use the JavaScript's built-in array constructor new Array(). Use [] instead. These two different statements both create a new empty array named points:
var points = new Array(); <== Bad
var points = []; <== Good
These two different statements both equally create a new array containing 6 numbers:
var points = new Array(40, 100, 1, 5, 25, 10) <== Bad
var points = [40, 100, 1, 5, 25, 10]; <== Good
As mentioned earlier in this tutorial, the new keyword complicates your code and produces nasty side effects. You can create an array with multiple elements, but if you create a new array with only one element, you will get a whole different situation:
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<body>
<h4>Using new Array with two items:</h4> <p id="demo"></p> <hr /> <h4>Removing one item from the new Array:</h4> <p id="demo1"></p> <script> var points = new Array(40, 100); // Creates an array with two elements document.getElementById("demo").innerHTML = points[0]; var points = new Array(40); // Creates an array with 40 undefined elements !!!!! document.getElementById("demo1").innerHTML = points[0]; </script> </body> |
Using new Array with two items:Removing one item from the new Array: |
