How do I return the response/result from a function foo that makes an asynchronous request?

How do I return the response/result from a function foo that makes an asynchronous request?

With below code, what I was expecting is “diameter-selected” class to be added to the button and then to run the synchronous ajax calls. But, it seems that ajax calls run before the “.addClass” command and since it is waiting the promise I guess, I see the button effect after ajax request is completed. When I added setTimeout to the ajax calls for 1 nano second, I see the button effect before ajax calls are completed. So, I solved my issue in a weird way but I want to learn if there is a more professional way to achieve this.

How do I return the response/result from a function foo that makes an asynchronous request?

How do I return the response/result from a function foo that makes an asynchronous request?

i am trying to scan qr code using browser camera stream and use the result to fetch records from data base using ajax. i have difficulty getting scanned value outside async function.

How do I return the response/result from a function foo that makes an asynchronous request?

How do I return the response/result from a function foo that makes an asynchronous request?

How do I return the response/result from a function foo that makes an asynchronous request?

How do I return the response/result from a function foo that makes an asynchronous request?