In a previous post, I wrote about how we can send data to a function for its use. So we know how to send data to a function. How do we get data back? This is where the ‘return‘ keyword comes into play. Let’s look at the syntax…
[code lang=”js”]
function foobar(someArg) {
// Write some code here that does stuff… return someValue;
}
[/code]
The return keyword sends the data back to where it came from. That is key to remember…the data always goes back to the spot from where the function was called. So in the example above, the value of the return variable of someValue would go back from where the function foobar() was called.
Another important functionality of the return keyword is that it stops the function and exits immediately. What does this mean? Well, you could have two return statements in a function inside of an if/else statement that stops the function conditionally. The syntax would look like this…
[code lang="js"]
function foobar(someArg) {
// Write some code here that does stuff...
if('this' === 'that'){
return valueOne;
} else {
return valueTwo;
}
}
[/code]Another side note...you can build functions that do not have a return statement. Just keep in mind that those functions will return undefined. This usually does not throw an error unless you have some logic flaw somewhere that expects a value, but it is good to keep in mind. I have found that most functions I build return a value but having no value returned is not uncommon.
Happy Coding!
Clay Hess