检查数组javascript中的变量

Question

Short code for checking if a variable also exists inside an array is needed. Im thinking something like this:

   var category='cars';
   if (in_array(category, some_array)){
       do stuff!
   }

Is there any such function in js?

Thanks

Answer 1

if (some_array.indexOf(category) >= 0) {
   // do stuff
}

(Ref: https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Array/indexOf )

Answer 2

There's no native "in_array"-function in JavaScript (as in PHP), check out this solution:

http://phpjs.org/functions/in_array:432

Also a search would have lead you here:

JavaScript equivalent of PHP's in_array()

Answer 3

if(some_array[category] !== undefined){
  // it's there
}