Array in JavaScript
An array is a collection of elements that use the common name to store all the elements. Array always start from Memory Location Zero. It is lengthy process to store huge elements in a separate variable; Arrays solve this problem by storing all the elements into one variable.
Types of Array
- One dimensional Array
- Multidimensional Array
One dimensional Array
Creating an Array
Array can easily be created in JavaScript either enclosing a comma-separated list of values in square brackets ([]), or using the Array () constructor.
Syntax
- let arr = new Array();
- let arr = [];
Example
- var myArray = [element0, element1, …, elementN];
- var myArray = new Array(element0, element1, …, elementN);
Accessing the Elements of an Array
Array can easily have accessed by their index using the square bracket notation and index is a number that represents an element’s position in an array.
Syntax
Array_name[index]
Example
myArray[0];
Example to call individual elements
let loops = [“for”, “while”, “do-while”];
alert (loops [1]);
Example to call all elements
let loops = [“for”, “while”, “do-while”];
for (let i = 0; i < loops.length; i++) {
alert( loops [i] );
}
We can also use for..of and for.. in loop in javascript to iterate all the elements
let loops = [“for”, “while”, “do-while”];
for (let loop of loops) {
alert( loop);
}
let loops = [“for”, “while”, “do-while”];
for (let key in loops) {
alert( loops [key] );
}
Multidimensional arrays
Multidimensional array is an array which have array inside array.
let matrix = [ [11, 42, 63], [47, 54, 68], [57, 87, 94]];
alert( matrix[1][1] );