Regarding the image carousel, setting up automatic playback issues:
If you use native JS code, I currently know two methods, the first one:

function next(){ 这里是代码，比如index++; } var timer=setInterval(next, 2000);

The second type (where oBtnNext refers to a button obtained):

oBtnNext.onclick=function(){ 这里是代码，比如index++; } var timer=setInterval(oBtnNext.onclick,2000);

Here comes the point. The question is, if jQuery($("#next") is equivalent to oBtnNext above)

$("#next").click(function(){ 这里是代码，比如index++; }

Why write

var timer=setInterval($("#next").click,2000)

or

var timer=setInterval($("#next").click(),2000)

is not allowed, but

var timer=setInterval(function () { $("#next").click() },2000);

But it works.