jQuery鼠标悬停和淡入功能

Question

I have these two functions that select tabs of mine on mouseover, the first one is for the left side:

$(function() {
        var $items = $('#vtab>ul>li' || '#vtab2>ul>li');
        $items.mouseover(function() {
            $items.removeClass('selected');
            $(this).addClass('selected');

            var index = $items.index($(this));
            $('#vtab>div' && '#vtab2>div').hide().eq(index).show();
        }).eq(0).mouseover();
    });

This one's for the right side:

 $(function() {
        var $items = $('#vtab2>ul>li');
        $items.mouseover(function() {
            $items.removeClass('selected');
            $(this).addClass('selected');

            var index = $items.index($(this));
            $('#vtab2>div').hide().eq(index).show();
        }).eq(0).mouseover();
    });

and then I have another function that fades the page in and out:

$(document).ready(function() { $("body").css("display", "none");

$("body").fadeIn(3000);

$("a.transition").click(function(event){
    event.preventDefault();
    linkLocation = this.href;
    $("body").fadeOut(2000, redirectPage);
});

function redirectPage() {
    window.location = linkLocation;
}

});

For some reason the second function only works WHILE the page is fading in, it stops working once the animation is done. The second function also works if I make the screen small enough that I can't see both of my vertical lists at the same time.

Does anyone know why this may be? I'm new to jQuery and I really don't know where to begin.

Answer 1

I believe your issue is incorrectly using javascript's boolean operators. $('#vtab>ul>li' || '#vtab2>ul>li');

Is equivalent to: $('#vtab>ul>li')

Because the generalized boolean of '#vtab>ul>li' is true and "||" is the javascript "or" operator and "or" short circuits on the first true it finds.

Some relevant truths:

true || true || true == true
false || true || false == false
false || 'hey there' || true == 'hey there'
'hey there' || true == 'hey there'
'hey there' && true == true
true && 'hey there' == 'hey there'