如何在不包含匿名函数的情况下为 jQuery 使用美元符号？

Question

There's a very common technique to write $ instead of jQuery and wrap it inside a function as such:

(function($) {
    //Code here
})(jQuery);

Now, the problem with this is that, you are inside a small, local scope and that's good, for the most part, but if you're trying to, say, call a function name dynamically by string-construction:

let dynamic_name = some_function_name; //but should be dynamic, duh
window[dynamic_name]();

Won't work because you're operating inside that local scope, not inside the window scope and it will not be able to find that function, example:

 (function($) { //If we put this outside of this scope, it works. function test() { console.log('test'); } let name = 'test'; window[name](); })(jQuery);

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

This also means that if your script gets used as a library, your functions are not callable, because you're wrapping them inside an anonymous function.

Exactly how do you get around this?

Answer 1

Either assign the function to window explicitly:

 (function($) { window.test = function test() { console.log('test'); } let name = 'test'; window[name](); })(jQuery);

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

Or put the function in an object instead:

 (function($) { //If we put this outside of this scope, it works. const fns = { test() { console.log('test'); } }; let name = 'test'; fns[name](); })(jQuery);

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

This doesn't really have anything to do with jQuery - the same sort of behavior (and solution) can be seen in any IIFE, or any block that's not on the top level.