JavaScript Array

An array is a single variable that can store multiple values of the same type at a time. Thus, a Javascript array is used to hold many values of the same type under a single name. These values can be accessed by referring to their index number. An array in Javascript can be constructed in many ways including;

By using an Array literal

Syntax:

var arrayName = [value 1, value 2, …];

By creating an instance of Array directly

Syntax:

var arrayName = new Array();

By using an Array constructor
An array in Javascript can also be constructed by creating an instance of the array by passing arguments in a constructor.

var arrayName =new Array("element1","element2",..."elementn");  

Example:

<html>
<body>
<script>
var myTeam=new Array("Jai","Navdeep","Shivanshu","Lalit");
for (i=0;i<myTeam.length;i++){
document.write(myTeam[i] + "<br>");
}
</script>
</body>
</html>

JavaScript Array Object Properties:

Property Description
constructor Returns a reference to the array function that created the object.
length It reflects the number of elements in an array.
prototype It allows us to add properties and methods to an object.

JavaScript Array Methods:

JavaScript Array concat() method:
Use: To return a new array object that contains two or more merged arrays.

Array copywithin() method:
Use: To copy the part of the given array with its own elements and return the modified array.

Array every() method:
Use: To determine whether all the elements of an array satisfy the provided function conditions.

Array fill() method:
Use: To fill elements into an array with static values.

Array filter() method:
Use: To return the new array containing the elements that pass the provided function conditions.

Array find() method:
Use: To return the value of the first element in the given array that satisfies the specified condition.

Array findIndex() method:
Use: To return the index value of the first element in the given array that satisfies the specified condition.

Array forEach() method:
Use: To invoke the provided function once for each element of an array.

Array includes() method:
Use: To check whether the given array contains the specified element.

Array indexOf() method:
Use: To search the specified element in the given array and return the index of the first match.

Array join() method:
Use: To join the elements of an array as a string.

Array lastIndexOf() method:
Use: To search the specified element in the given array and return the index of the last match.

Array map() method:
Use: To call the specified function for every array element and return the new array.

Array pop() method:
Use: To remove and return the last element of an array.

Array push() method:
Use: To add one or more elements to the end of an array.

Array reverse() method:
Use: To reverse the elements of the given array.

Array shift() method:
Use: To remove and return the first element of an array.

Array slice() method:
Use: To return a new array containing the copy of the part of the given array.

Array sort() method:
Use: To return the element of the given array in a sorted order.

Array splice() method:
Use: To add/remove elements to/from the given array.

Array unshift() method:
Use: To add one or more elements at the beginning of the given array.