An introduction to the various methods of defining arrays in javascript and the common functions

Definition of array:
Method 1.

var mycars=new Array()
mycars[0]="sharejs.com"
mycars[1]="Volvo"
mycars[2]="BMW"

Method 2.
Definition and initialization together:

var mycars=new Array("Saab","Volvo","BMW");

Or:

var mycars=["Saab","Volvo","BMW"];

Javascript two-dimensional array, with a one-dimensional array to simulate:
Method 1.

var   arr   =   new   Array(['a','b','c'],['d','e','f']);

Arr [0] returns the first one-dimensional array, and arr[0][0] returns the first element of the first one-dimensional array 'a', the same below.
Method 2.

arr=new   Array();   
for(i=0;i<100;i++) {   
     arr[i]=new   Array(...);   
}

Method 3.

var  arr=new  Array(   
  new   Array(),   
  new   Array(),   
  new   Array()   
);

Javascript arrays do not need to be set in length, they are expanded by themselves, and the array name.length returns the number of elements

Common javascript array functions:
ToString () : converts an array to a string
ToLocaleString () : converts an array to a string
Join () : converts an array to a symbolically concatenated string
Shift () : removes an element from the head of the array
Unshift () : inserts an element at the head of the array
Pop () : removes an element from the end of the array
Push () : adds an element to the end of the array
Concat () : adds elements to an array
Slice () : returns the part of the array
Reverse () : reverse sort the array
Sort () : sort an array
Splice () : inserts, removes, or replaces an array element