Ajax advice for WordPress Widgets

Dear WordPress Community,

I have been searching the internet for a solution to this problem but I haven’t found an adequate solution. Basically I want to use jQuery to accept form input on a widget and post the data to the same plugin and deliver the response without reloading the page, so Ajax.

I have found a few guides to do this; the problem I am running into is that my admin settings page for the widget contains login information that is required for the form processor function to function. My login data is currently stored in the $instance array along with the other widget settings.

What is the best solution to accessing the $instance array to get the authentication information so that I can register the form processor function with the Ajax handle outside of my sub-class?

Any ideas?

Note: I am a PHP developer that is new to creating WordPress plugins.

Thanks.