JavaScript Function: Study Note for Arguments

Most time we want to write functions that take inputs.

function doSomething(input) {
console.log(run some code);
}

This syntax to say that a function is expecting something to be passed in that it's expecting an argument looks like this rather than an empty "()".

For example, if we want to calculate square, we can write it in function.

function square(num) {
console.log (num * num);
}

Here, we give a name "num" for the input, but you can give any name you want.

Then we give a number in the "()", then call the square(10), so we get the result 100.

It also works for the string. For example, if we want to say hello to someone, we can use function.

function sayHello(name) {
console.log ("Hello" + name + "!");
}

We call sayHello ("Tom"), it gives us Hello Tom!

Functions can have as many arguments as needed. For example, if we want to calculate area, we can give two inputs: length and width, and then run the code.

Arguments are one of the important pieces and functions that make them really useful because it is not only about shortening our code and repeating the same chunk of code every time. It is also about making that code change a little bit depending on some inputs.

Comments

Intermediate Express.Js: Write Conditions and Loops In The EJS (study note)

We continue to use the app.js which we have build to be the study example. In the last post, we only add a simple EJS tag <%= thingVar %> inside h1 tag. This will match the "thing" to any "thing" request from the user. If Statement Today, the course shows us to write a simple if statement in the EJS file. I learn to apply it to my own app. In the if statement, if users send"/wantto/workout" request, the page will show a new content "Good Idea!". We wrote the if statement in the "diet.ejs" file, and we add "<% %>" tags around the code. We have to wrap every line of JavaScript anytime JavaScript starts and ends. Moreover, you may see there are two types of ejs tags here: <%= %> The one with equal sign. According to the course, when we add equal sign, the value that is returned inside of the tag will be rendered to the HTML page. it will be added to the HTML. For example, if we write ...

Intermediate Express.js: How To Add Styles & Partials in EJS File?

So far, we only have simple HTML tags and ejs tags in each ejs file. Every template page has no style at all. And the basic HTML header and footer are also missing. Today, I learned how to add styles and partials in ejs file. Link Style Step One: Touch a Separate CSS file I create a new directory "Style" under the "EJSDemo" directory, then I add a new CSS file "app.css" inside "Style" folder. Step Two: Add app.use(express.static()) in the app.js I add app.use(express.static("style")) in the "app.js". This will tell Express.js to serve the content of "Style" directory. Step Three: Write styles in CSS file I simple give body an orange background color and set text color to be grey. Step Four: Link to CSS file in the EJS file I just add <link> tag to link the "app.css" file on the top of the h1 tag in each ejs template. As the result, when I run the app and...

GIT Study Note: Six Git Commands You Should Know!

What is Git? According to Git website , Git is a free and open source distributed version control system designed to handle everything from small to very large projects with speed and efficiency. Basically, we can use Git to track all of changes and revert them back if we made mistakes. The version control system is a way for us to work with different versions of our code, so that we can save different features and make notes as we progress. It is also very useful for team collaboration. Six Git Command You Should Know 1. Git Init In our server, we need to create a "Git" directory and inside of "Git", we make another direcory "git_inro". Then, we add a file "app,js" in the "git_intro" folder. The first thing we need to run is "git init" . When we run git init, it will make a directory which is hidden called ".git". Wherever I run that git init command, it's going to track all of our changes. ...

Learn Bootcamp From Zero

Search This Blog