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Write a Conditional Statement: else

3:30 with Guil Hernandez

You'll often hear conditionals referred to as if/else statements. In this video, we'll provide code that runs only if a condition is false, using an else clause. It's optional, but is often used as a "fall back" for when a condition isn't true.

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What is the ${} syntax?
The expression inside ${…} is evaluated and the result becomes a part of the string. We can put any valid expression inside ${…}: a variable like playerName or an arithmetical expression like 1 + 2 or something more complex.

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    You'll often hear conditionals referred to as if else statements. 0:00
    So finally we'll provide code that runs only if the condition is false, 0:04
    using an else clause. 0:09
    It's optional, but an else clause is often used as a fallback for 0:10
    when a condition isn't true. 0:15
    You add it to a conditional statement like this. 0:17
    Type the keyword else, and the code you want to run if the condition is not 0:19
    true goes inside a pair of curly braces. 0:24
    Inside the curly braces, I'll type console.log, and 0:27
    we'll print a message to the console saying that a movie title was sold out. 0:31
    But this time I'll do things differently. 0:37
    Instead of using quotes and the plus symbol like this to combine multiple 0:39
    strings into one, I'll use what's called a template literal. 0:44
    To complete a template literal, instead of single or double quotes, 0:48
    you use the ` character. 0:53
    So inside the back ticks, I'll type, Sorry, the movie. 0:55
    And you no longer need to use a plus symbol to insert a value 1:01
    of the variable or property into the string when you use a template literal. 1:05
    Instead, you wrap the property inside a dollar sign and a set of curly braces. 1:10
    The ${} syntax will insert the value into the string, 1:17
    which in our case will be the value of the title property, 1:23
    so let's do movie.title. 1:28
    And we'll follow that with, is sold out. 1:31
    All right, so, as you can see, 1:38
    template literals offer a lot of convenience when creating strings. 1:40
    They're easier to write and read. 1:44
    So finally, I'll change the strings inside the if 1:46
    statement to a template literal too. 1:50
    First, I'll remove all the quotes and plus signs inside the console.log. 1:53
    Then place back ticks around the message, and add a dollar sign and 2:04
    curly braces around movie.title and movie.time. 2:09
    All right, I'll give main.js a save, head over to the browser, 2:17
    refresh the page, and good. 2:22
    In the console, we see the sold out message for 2:24
    Wonder Woman and Black Panther only. 2:28
    And that's right, because their status properties are unavailable. 2:31
    While the rest of the titles show the available show times. 2:37
    So Avengers, The Last Jedi, and Lady Bird all have their status set to available. 2:40
    That was a lot of information to take in. 2:49
    I just wanted to show you what's possible using basic JavaScript features like 2:51
    variables, arrays, objects, loops, and conditionals. 2:55
    If you didn't understand everything or think that you can't 2:58
    remember everything I covered, don't worry, that's completely normal. 3:00
    In fact, most programmers don't remember everything either. 3:04
    It's common to head over to Google or a resource like Mozilla Developer Network 3:07
    frequently to get a refresher on how these features work. 3:11
    This was just a tiny first step into the world of JavaScript programming. 3:15
    You're not going to immediately power robots, space suits, and 3:18
    rocket ship interfaces with what I just covered. 3:22
    But once you've got the basics down, 3:24
    you could work with JavaScript in all sorts of fascinating ways. 3:26

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