Year: 2021

Home » 2021

PHP include – How to Use It, With Examples

by
How to use PHP include

The PHP include expression allows you to import code from another file and import code from external PHP libraries. Here’s how to use it, with examples. PHP include will execute and import PHP code from another file or library.  It allows you to re-use code and work with libraries provided by others – for example, you may download a library to interact with a mapping service and wish to include it in your code. Syntax include ‘./path/to/file.php’; Simple! The include expression must be followed by the … Read more

Categories PHP

Home » 2021

JavaScript Callback Functions How-To, With Examples

by
JavaScript Callbacks

This article will explain callback functions in JavaScript – what they are, why they’re used, and how to use them. What is a Callback in the JavaScript Programming Language? A callback function is a function that is passed as a parameter to another function to be executed from within the second function. What are Callbacks Useful For? Callback functions are usually used to execute a function when another has been completed. This allows for easy code- reuse. A single function that accepts a callback can be … Read more

Home » 2021

Math/Arithmetic in Bash/Shell Scripts, With Examples

by
Bash Math & Arithmetic

Math is easy, Bash scripting is easy, so performing math/arithmetic in Bash/Shell scripts should be easy too. It is. Here’s how to do it. Working with Integers Bash’s built-in arithmetic can only handle integer (whole number) values. If you attempt to declare a variable with a non-integer value: declare -i e=2.5 You’ll see the following: bash: declare: 2.5: syntax error: invalid arithmetic operator (error token is “.5”) To work with non-integer numbers, you will need to use an external program to perform your calculations – but first, … Read more

Home » 2021

Variables in Bash/Shell Scripts and How To Use Them [Tutorial]

by
Bash Variables and How to Use Them

This article will show you how to use variables in Bash and Shell scripts in Linux. Bash (or Linux Shell) scripts are files you write containing commands to automate common tasks and save yourself some time. Variables are things in scripts that hold a value for later use – a number, or a filename, or anything, really. Here’s how to define and use variables in Linux Shell scripts. These examples should work in the most popular Linux Shells, Bash, and Zsh. Declaring Bash Variables Bash VARIABLES ARE UNTYPED … Read more

Home » 2021

jQuery vs JavaScript – Differences? Which is Better?

by
jQuery vs JavaScript

This article will explain what JavaScript and jQuery are, how they differ, and how/why they should be used. What is JavaScript JavaScript began life in the mid-1990s as a scripting language for adding interactivity to web pages. Over time it has been developed into a full-featured programming language, which can even be run outside the web browser (more detail on this in our Node.js article). You can also see our article outlining the differences between JavaScript and Typescript here. What is jQuery? jQuery is a library written in JavaScript. … Read more

Home » 2021

DIY Raspberry Pi/Python Powered PACHINKO [Kitchen Build]

by
Raspberry Pi Python Pachinko

Pachinko? Pichinko? Pychinko? I’ve been playing around with is idea for a while because… I don’t know; it seemed like a cool concept. That’s my whole motivation. Here’s a Raspberry Pi and Python-powered pachinko machine. This project is really basic, so it’s good for beginners, and the result is a lot of fun to mess with and would make a good desk ornament to fidget with or something for the kids to build on a rainy day to learn about coding and circuits and all … Read more

Home » 2021

How to Refresh the Page in JavaScript using location.reload(), With Examples

by
JavaScript Refresh Page

Here’s a short guide to refreshing a webpage with JavaScript, with examples. There are over 500 ways to trigger a page reload using JavaScript. All but one are unofficial or are the side effect of another behavior. Here’s how to do it properly. Using location.reload() Simply call: location.reload() …anywhere in your code to trigger a page reload. It’s that easy. What about window.location.reload() ? You may see some use: window.location.reload() This is exactly the same as using location.reload() – the window object in JavaScript is the global context, so there’s usually no … Read more

Home » 2021

Compare JavaScript Dates (Day/Minute/Hour/Before/After), With Examples

by
JavaScript Compare Dates

Following on from our article on adding and subtracting time from dates in JavaScript – here’s how to compare two JavaScript date objects. This article will explore comparing dates/times with different granularity levels – from dates that are an exact month to dates that fall in the same year. Using Boolean Operators Native Javascript date objects can be compared using standard boolean/comparison operators – allowing you to compare dates by checking whether they are equal, not equal, greater than, less than, equal to or greater than, or equal to or … Read more

Home » 2021

How to Use Functions in Bash/Shell Scripts, With Examples

by
Bash Function Uses

This article will explain how to use functions in Bash scripts – helping you to reuse your code and simplify your scripts. Why write code multiple times when you can write it once and re-use it? That’s what functions let you do. This article outlines the use of functions in Bash/Shell scripts. What is a Function? A function is a piece of re-usable code. Functions can accept parameters, which allow them to perform the same repeatable actions on different inputs. Functions usually perform any action, output or print results, or return … Read more

Home » 2021

Using the ‘sed’ Command in Bash/Linux, With Examples

by
Bash sed command

The sed (Stream EDitor) command in Bash/Linux reads text from a stream or file and performs line-by-line operations on it based on a set of supplied criteria.  Here’s how to use it. sed is an automated way to process text. One simple example of where sed can be used is doing a simple find-and-replace for a word in a text document – the text with the words replaced can then be saved to a new file or overwrite the original. Why? Being able to modify text – either from a … Read more