jquery - Javascript shorthand if

Question

if (event.keyCode === 38 || event.keyCode === 33 || event.keyCode === 40 || event.keyCode === 34) {
}

How to shorthand this code? Remember that conditional switch statements are slow.

I want to do something like

if (event.keyCode === 38 || 33 || 40 || 34)

Answer 1

I actually recommend using a switch. The general rule of thumb is

• 1 or 2 values: use an if
• 3 to 10 values: use a switch
• 11 or more: use an array lookup

But since you're using jQuery, you can simply do:

jQuery.inArray(event.keyCode, [38,33,40,34])