Using JQuery to change order of elements

问题:

Does anybody know what I'm doing wrong? I'm trying to alter the order on which some images show, I want the images to shift to the right/left one spot every time I hit a button. This is what I've tried but no luck.

Any help or insight will be truly appreciated

$("#rightShift").click(function(){
    $("img").hide();
    var count = $("img").size();
    $("img").each(function(i) { 
        var indexImg = count - i;
        $("img:eq(indexImg)").show();
    });
}); 
$("#leftShift").click(function(){
    $("img").hide();
    $("img:last").prependTo("img");
    $("img").show();
});

回答1:

Assuming you want this to work like a carousel that goes around (the last image become the first one when you are shifting right), then this is how I would do it:

$("#rightShift").click(function(){
    $("img:last").detach().insertBefore("img:first");
});

$("#leftShift").click(function(){
    $("img:first").detach().insertAfter("img:last");
});

回答2:

You're trying to refer to a variable inside a string. That makes no sense.
You actually meant:

$("img:eq(" + indexImg + ")").show();

But a more efficient implementation is:

$(this).prev().show();

The most efficient implementation without side-effects is:

$("#rightShift").click(function(){
    var $images = $("img"); // <-- Reference to all images
    $images.hide();
    //var count = $images.length; //<-- Unused variable, delete it?
    $images.each(function(i) { 
        $(this).prev().show();
    });
}); 
$("#leftShift").click(function() {
    var $images = $("img");
    $images.hide();
    $images.last().prependTo("img"); // OR: $images.before($images.last());
    $images.show();
});

回答3:

This:

$("img:eq(indexImg)").show();

Should be this:

$("img:eq(" + indexImg + ")").show();

Not sure if other stuff is wrong though.