How to

A collection of 87 posts

Node

How to validate a URL with Node JS

Recently I needed to validate http links with Node. I thought this should be easy, and it is. Luckily for us, Node has a built in URL module that can help us to this. This is the snippet(not the final one): const URL = require('url').URL // 1

How to

Go: Read a file line by line

In this tutorial we will look at how we can read a file line by line using Go. Go makes this incredibly easy by using bufio.NewScanner(). You can find the full source code here [https://github.com/programmingwithswift/ReadFileLineByLineWithGo]. Ok, let's jump in. Create package and import

Python

Python list all files in directory and subdirectories

Getting a list of all files in a directory and its subdirectories can be quite a common task, so, in this tutorial I will show you how you can do this with 4 lines of code using os.walk. Below you can see how we can recursively loop through all

TypeScript

How to compare dates with TypeScript or JavaScript

In this tutorial we will learn how to compare dates with TypeScript or JavaScript. Working with dates can be a painful experience but comparing them is not too bad as it works the same way as general object comparisons. We will start by looking at dates and how they work

JavaScript

How to pretty-print JSON with JavaScript

In this tutorial I will show you how you can pretty print a JSON string. It is a one liner, but it makes all the difference. Normally when we use JSON.stringify, we only want to serialise a JSON object, but sometimes after we serialise it, we might want to

Node

How to Read and Write JSON with NodeJS

In this tutorial we will go over how read and write a JSON file with NodeJS. It should come at no surprise that Node makes working with JSON extremely easy, and with the built in fs module, reading and writing to the file system is equally easy. This tutorial is

How to

How to find duplicates in an Array with JavaScript

In this tutorial I will show you how you can check if an Array contains duplicate elements, but also, we will look at how you can return the elements that are duplicates. Both techniques focussed around the Set data type. Let's start with the data that will use

How to

How to get the index from for-of loop with JavaScript

In this tutorial I will show you two ways that you can get the index when using a for-of loop. Let's start with the data that I will be using: const shoppingList = [ 'bread', 'milk', 'pie', 'juice' ] Option 1: .keys() The

JavaScript

How to run Async Await in Parallel or serial with JavaScript(Node)

In this tutorial I will show you how you can easily run async/await in parallel. It seems to me that we often forget the power of async await, which comes from being able to run multiple async tasks/jobs/functions at the same time. In order for us to

SwiftUI

Numbers only TextField with SwiftUI

Requiring an input to be numbers only is quite a common task. In this tutorial I will show you how to allow numbers only in a TextField using SwiftUI. Step 1: Change the keyboard type to .decimalPad The first step in this task is to change the keyboard type to

How to

How to ignore/skip or run only one test with Jest

In this tutorial I will show you how you can skip certain tests, or, run only specific tests with Jest. Recently I needed to do this at work, but I always used to comment things out, which can become frustrating, but then I found out that one can skip or

How to

How to change remote origin url for Git repo

In this tutorial I will show you how you can change your git repo's remote origin url. Let's get started. I have created a test repo on GitHub to use in order to go through the steps. What I will be simulating in this tutorial is

How to

Could not open a connection to your authentication agent

In this post I will go through ways to fix the error: connection to the authentication agent. This issue is incredibly irritating when you haven't encountered it before, but the problem is simple, basically the ssh-agent is not running. We need to ensure that we start the ssh-agent

JavaScript

How to convert a byte array to String with JavaScript

In this tutorial I will show you how you can convert a byte array to a string using JavaScript. I was busy with a task recently that required me to do this, luckily, JavaScript makes this easy with the built in String.fromCharCode() function. Let's see how we

How to

How to add a delay to code in Swift

In this tutorial you will learn how to add a delay to your code. To add a delay to your code we need to use GCD. GCD has a built in method called asyncAfter, which will allow us to run code after a given amount of time. The code is

Swift

How to convert Dictionary to Json with Swift

It is a common task to convert a Dictionary to JSON. In this tutorial I will show you how you can do just that, luckily for us, Swift makes this incredibly easy. A quick note before we get started, the dictionary's value needs conform to Encodable or Codable.

Swift

How to replace characters in string with Swift

In this tutorial you will learn how to replace characters in a String using Swift. We will be using the following methods replacingOccurrences, replacingCharacters as well as replaceSubrange. Replace characters with replacingOccurrences method The first method we are going to look at is replacingOccurrences. Two things to note about this

Xcode

How to screenshot or record a video in the iOS simulator

Taking a screenshot or recording a video of the iOS simulator can sometimes be useful, whether it is for the App Store or maybe for some internal use case that the company or your team has. In this tutorial I will show you how you can take a screenshot with

Xcode

How to tell what version of Swift Xcode is using

Sometimes we need to check what version of Swift we are using, or, more correctly what version of Swift Xcode is using. There are two ways that we can do this, one is more accurate if you want more than just the major version. Finding Swift version using the terminal

Flutter

How to save a file locally with Flutter(Image, Text)

In this tutorial you will learn how you can save a file locally. Flutter has a built in type called File which will allow us to read and write to a file locally. To make our lives easier we do need to add a package, the path_provider package, which

Flutter

How to remove debug banner with Flutter

In this tutorial you will learn how to remove the debug banner from your Flutter app. I find this debug banner to be quite annoying but luckily there is a one line fix for it. To remove the debug banner set the following property on your MaterialApp widget: debugShowCheckedModeBanner: false,

SwiftUI

How to make SwiftUI view fill width or height of screen

In this tutorial I will show you how to make a view fill the width or height of the parent view or fill the screen. It is often required that a view fill a space, whether it is width, height or both. Luckily for us SwiftUI makes this very easy

How to

How to get index and value from for loop with Swift

Sometimes I find that I need to get both the index and the value when I am looping through an array. In this tutorial I will show you how to get both. I have the following array of programming languages: let languages = ["Swift", "Kotlin", "JavaScript&

Flutter

Change button color on press with Flutter

In this tutorial I will show you how you can change the color of a button when a user presses it. To demonstrate this I will be using a RaisedButton. Toggle button color change on press class _MyHomePageState extends State<MyHomePage> { // 1 bool _hasBeenPressed = false; @override Widget build(

UserDefaults

How to store a date in UserDefaults with Swift

UserDefaults can be a useful tool to store small amounts of information. In this tutorial I will show you how you can store a Date in UserDefaults using Swift. Storing a date in UserDefaults Below is the code that we will use to save the date: let defaults = UserDefaults.standard