if you have a array like ('a', 'b') and check $.inArray('a', thearray); you get the index, which is 0, and could be false. So you need to check the result further and it's annoying...
Is there a quick method trough which I can get only true/false, and not the indexes?
basically I have a string in a html5 data attribute: data-options="a,b,c" and 3 a, b, c variables in javascript that must take true/false values based on what's inside data-options...
You can achieve that by invoking the binary NOT operator.
if( ~$.inArray('a', thearray) ) {
}
Explained in detail here: typeofnan.blogspot.com/2011/04/did-you-know-episode-ii.html
!!~$.inArray('a', thearray)!! forces the result to be a boolean value. So -4 or 11 for instance would get turned into true, whereas 0 for instance gets turned into false. Anyway, I don't recommend it here, since it looks pretty alien :-)
a = !!~$.inArray('a', thearray); :D thanks!Test against -1:
$.inArray('a', arr) !== -1
The above expression will return true/false.
Because JavaScript treats 0 as loosely equal to false (i.e. 0 == false, but 0 !== false), if we're checking for the presence of value within array, we need to check if it's not equal to (or greater than) -1.
Yep, compare to -1.
if ($.inArray('a', thearray) === -1) {
// not found
}
You could wrap that into another function if it really bugs you:
function myInArray(needle, haystack) {
return $.inArray(needle, haystack) !== -1;
}
