Arrays are one of the commonly used data structures in the field of computer science. They are mainly used for mutation operations. example:
let marks=[20, 40, 50, 60];
Arrays can also contain items that are of different data types. For example this array:
let studentDetails = [20, 'Mike Collins', 'Third year']
contains both numbers and strings.
There are two main ways of accessing array items.
The Dot Notation.
Bracket Notation
This article talks about arrays and common array operations.
Common Operations
Create an array
let programmingLanguages = ['JavaScript', 'Java', 'Python', 'Ruby', 'PHP'];
Find the length of array
console.log(programmingLanguages.length);
// 5
Accessing an array items using the index:
let firstLanguage = programmingLanguages[0];
//JavaScript
Find the last item in an array
let lastLanguage = programmingLanguages[programmingLanguages.length - 1]
//PHP
Loop over an Array
programmingLanguages.forEach((language) =>{
console.log(language);
//JavaScript
//Java
//Python
//Ruby
//PHP
});
Add an item to the end of an Array
programmingLanguages.push('Go');
console.log(programmingLanguages);
//['JavaScript', 'Java', 'Python', 'Ruby', 'PHP', 'Go']
Remove an item from the end of an Array
programmingLanguages.pop();
console.log(programmingLanguages);
//['JavaScript', 'Java', 'Python', 'Ruby', 'PHP']
Remove an item from the beginning of an Array
programmingLanguages.shift();
console.log(programmingLanguages);
//['Java', 'Python', 'Ruby', 'PHP']
Add an item to the beginning of an Array
programmingLanguages.unShift('Go');
console.log(programmingLanguages);
//['Go', 'Java', 'Python', 'Ruby', 'PHP']
Find the index of an item in the Array
programmingLanguages.indexOf('Python');
//2
Remove an item by index position
let removedLanguage = programmingLanguages.splice(pos, 1);
console.log(removedLanguage);
//Java
Copy an Array
let arrayCopy = programmingLanguages.slice()
This article was target towards helping beginners to get started with arrays and common array operations.
Find a more detailed explanation on arrays here: MDN
Thank you for reading.