Essential JavaScript

Going Further

Blocks

One way to organize our code is to use blocks.

A block statement is a way to group other statements together.

We have already used block statements while working with if statements:

var x = 2; if (x < 4) { x++; }

The truth is, those curly braces and everything in between them are a single JavaScript statement!

Why Blocks?

An if statement only applies to a single statement. We could have written the above example this way:

var x = 2; if (x < 4) x++;

However, the curly braces of a block statement are widely considered easier to read, even if they involve more lines.

Besides, if we need to execute two or more statements together, we need to use a block statement to group them anyway:

var x = 2; var y = 4; if (x < y) { x++; y--; }

Using block statements with if, else if, else, and similar statements is a best practice.

Arbitrary Blocks

We can also create arbitrary blocks of code without any if, else if, or else statement:

var x = 2; var y = 4; { x++; y--; }

Without a conditional statement in front of it, the block statement will always run.

Next, we will learn how to use block statements to keep our variables organized.

Learning Goals

  • I know what a block statement is

  • I can group multiple statements with a block statement

  • I know it is best practice to use curly braces with if, else if, and else statements

Code Editor

Click "Run Code" to execute your JavaScript in a secure sandbox and see the output below.

Console Output

// Console output will appear here...

0 output lines