JavaScript array explanation (how to declare and calculate arrays)

1. array declaration method

(1): arrayObj = new Array (); // create an Array

Var arr1 = new Array ();

(2): arrayObj = new Array ([size]) Create an Array and specify the length. Note that the length is not the upper limit.

Var a = new Array (5 );

(3): arrayObj = new Array ([element0 [, element1 [,... [, elementN]) Create an Array and assign values

Var a = new Array (["B", 2, "a", 4,]);

(4): arrayObj = [element0, element1,..., elementN]

Var a = ["B", 2, "a", 4,];

(Note): note the difference between "[]" and "[]".

Var a = new Array (5); // creates an Array of 5 characters.

Var a = new Array ([5]); // creates an Array with a length of 1 and a first value of 5.

2. Array Operation (Transfer address)

Var t2 = new Array (); t2 [0] = 1; t2 [1] = 2; test2 (t2); // transfer address (Array) function test2 (var2) {for (var I = 0; I <var2.length; I ++) {var2 [I] = var2 [I] + 1 ;}} for (var I = 0; I <t2.length; I ++) {alert (t2 [I]);}

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