空主体的JS（jQuery）函数

Question

I have a function in the code that wasn't written by me.

$("*").not("a, li, ul").click('click', function(){})

This function replaces event listeners on empty string or what? What is the purpose of making functions with empty body. Is any other way to write things clear?

Answer 1

It does nothing. It doesn't add something, nor does it remove something. It's just wasted internet traffic bytes because more data has to be downloaded by the client. See below, it still executes all:

 $('#a').click(function() {alert("foo")}); $('#a').click(function() {}); $('#a').click(function() {}); $('#a').click(function() {}); $('#a').click(function() {}); $('#a').click(function() {alert("bar")}) 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div id="a"> a </div> 

There's no purpose of adding empty listeners what so ever.