• Js Node Practice Lab

    By

In our effort to familiarize ourselves with the Learn IDE, Let's play with strings and numbers again but in the Learn IDE. First things first though, let's open this lab in the Learn IDE. Go ahead and click the blue "Open" button at the top of this page. You should then be whisked away to the IDE.

Alright! This lab is very important. I'm going to teach you how to approach all labs...and really everything in coding. That's a huge statement, but programming is actually fairly simple if you follow this process.

First things first, let's run the code we are given. That should always be your first task. Just like when you are using a map to find a new restaurant, you need to know where you are now before you can know where you need to go. To run the code, type nodejs index.js in your terminal. You should get something like this:

Name:
Joe
Height:
74

Look familiar? Open up the index.js file and take a look. No HTML here, but you can see some basic things. The first two lines of code are below:

var name = "Joe"
var height = "74"

These two just assign the value "Joe" and "74" to name and height, respectively. name and height are variables. "Joe" and "74" are Strings. We know they are Strings because they are wrapped in quotes. The next four lines do all of the outputting to your terminal.

console.log("Name:")
console.log(name)

console.log("Height:")
console.log(height)

The first two at first print the String "Name:", then it prints the value inside name. Earlier in our program, we assigned name a value of "Joe". So, it prints out Joe. Nice! What if we put name in quotes?. Give it a try, then run your program again by typing nodejs index.js. You should see it print out the literal name instead of Joe. You just converted name from a variable into a String. Remove the quotes and everything will work again.

Ok, go ahead and change the name variable to your name. To do this, modify the first line to something like this var name = "Janet". Re-run your code and you'll see everything gets updated. Awesome.

Finally, we are going to modify our height. You could modify the height the same way we modified name. Simply change the "74" to whatever your height is. Remember last time though? We wanted to just have you "grow" by adding 1 to our current height. We can try that out by modifying the console.log(height) line by writing console.log(height+1). If you re-run that code you'll see it just appends 1 to the end of whatever height you had. That's not what we want! We want proper addition
to occur. Just like last time, we need to translate our String ("74") into a number. You can do this in your console.log like this: console.log(parseInt(height) + 1 ). That converts "74" into a number and then adds one. If you re-run the code now you'll see that it works! The other way we can modify this is to change the assignment of the variable in the first place. So let's modify the var height = "74" line to look like this

var height = 74

Boom! We took away the quotes and now it's a number not a string. You can remove the parseInt part of your console.log to look like this: console.log(height + 1) and everything should work properly.

Now it's time to submit your work back to learn. Go ahead and run learn submit in the terminal. You should then get a few more green lights and be ready to move on to the next lesson. Congratulations

View Node Practice on Learn.co and start learning to code for free.

Learn at Flatiron School

All of our students learn with our custom-built, state-of-the-art online learning platform designed to connect you to other students and instructors in real time.

Our NYC programs are held in a vibrant, 20,000 square foot campus in Manhattan's Financial District. Our campus encourages colalboration and jumpstarts creativity.

Our students learn with real tools, in groups that simulate development teams. Our graduates learn how to self-teach, ask the right questions, and collaborate with others.