What is "?:" notation in JavaScript?

Question

I found this snippet of code in my travels in researching JSON:

var array = typeof objArray != 'object' ? JSON.parse(objArray) : objArray;

I'm seeing more and more of the ? and : notation. I don't even know what it is called to look it up! Can anyone point me to a good resource for this? (btw, I know what != means).

Answer 1

It's the ternary conditional operator -- basically,

if (condition) {
   a = 4;
}
else {
   a = 5;
}

becomes

a = condition ? 4 : 5;

Answer 2

It's called a Conditional (ternary) Operator. It's essentially a condensed if-else.

So this:

var array = typeof objArray != 'object' ? JSON.parse(objArray) : objArray;

...is the same as this:

var array;
if (typeof objArray != 'object') {
    array = JSON.parse(objArray);
} else {
    array = objArray;
}