"elseif" syntax in JavaScript

javascript if-statement syntax
Hari Gillala picture Hari Gillala · Oct 23, 2010 · Viewed 382.4k times · Source

How can I achieve an elseif in a JavaScript condition?

Answer

Jeff picture Jeff · Oct 23, 2010

In JavaScript's if-then-else there is technically no elseif branch.

But it works if you write it this way:

if (condition) {

} else if (other_condition) {

} else {

}

To make it obvious what is really happening you can expand the above code using an additional pair of { and }:

if (condition) {

} else {

   if (other_condition) {

   } else {

   }

}

In the first example we're using some implicit JS behavior about {} uses. We can omit these curly braces if there is only one statement inside. Which is the case in this construct, because the inner if-then-else only counts as one statment. The truth is that those are 2 nested if-statements. And not an if-statement with 2 branches, as it may appear on first sight.

This way it resembles the elseif that is present in other languages.

It is a question of style and preference which way you use it.

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