Why doesn’t inArray detect capital letters?

Question

I don’t understand why when I look for PALAVRA the inArray() jQuery does not find it. But if I look for palavra is positive when the array is PALAVRA.

The first test I expected to be positive does not work, why? In the manual it says that the comparison of values is strict, which means in this case?

var titles = ['{EXTENSIONS}', '{dummy}'];

var title1 = "{EXTENSIONS}";
if( $.inArray( title1, titles ) ) {
    $('#txt1').text('No!'); // Não entra
}

var title2 = "{extensions}";
if( $.inArray( title2, titles ) ) {
    $('#txt2').text('Yes!'); // Entra
}

var title3 = "{dummy}";
if( $.inArray( title3, titles ) ) {
    $('#txt3').text('Yes!');
}

Jsfiddle

Answer 1

The problem is that the inArray does not give a boolean as the name suggests. It gives the element’s input in the array.

In your first case it gives 0, hence the if fail.

In the second case where the if gives true, using "{extensions}" with small letter, this element does not exist in the array, hence the -1, and the if resolve true.

If we take a look at the source code:

inArray: function( elem, array ) {
    if ( array.indexOf ) {
        return array.indexOf( elem );
    }
    for ( var i = 0, length = array.length; i < length; i++ ) {
        if ( array[ i ] === elem ) {
            return i;
        }
    }
    return -1;
},

Apparently the vMore modern ersão has this code (below) but which is essentially identical:

inArray: function( elem, arr, i ) {
    return arr == null ? -1 : indexOf.call( arr, elem, i );
},

So in your code you can replace the ifs for:

if( ~$.inArray(valor, array) ){
// ou
if($.inArray(valor, array) > -1){

Example: http://jsfiddle.net/1ubr2gsn/3/