Useful Array Functions in JavaScript and C#

How to check if array contains a specific item

To check if an object or item is contained in a JavaScript array, you can use the includes function, like so:

const customerIds = [1, 2, 3, 4, 5];
console.log('IsIncludedInArray', customerIds.includes(3));

To do the same thing in C#, you can use the Contains or Any LINQ method, like so:

var customerIds = new int[5] { 1, 2, 3, 4, 5};
Console.WriteLine("IsIncludedInArray " + customerIds.Contains(3));
Console.WriteLine("IsIncludedInArray " + customerIds.Any(n => n == 3));

How to filter out contents in an array

To filter out the contents of an array in JavaScript, you can use the filter function., like so:

const customerIds = [1, 2, 3, 4, 5];
const filteredCustomerIds = customerIds.filter(n => n <= 3);
console.log('Filtered CustomerIds', filteredCustomerIds);

To do the same thing in C#, you can use the Where LINQ method.

var customerIds = new int[5] { 1, 2, 3, 4, 5};
var filteredCustomerIds = customerIds.Where(n => n <= 3);

foreach (var n in filteredCustomerIds)
{
  Console.WriteLine(n);
}

Tags: #JavaScript #CSharp #DotNet

Discuss... or leave a comment below.