call JS from Delphi code

There are many examples of the reverse, but none that gives you ability to call a JS function on a page from Pascal. Is it possible?

For instance, I want to submit a form. Which I have just dynamically created on the page.

I know that if I add some OnLoad JS somewhere and click some button synchronously, it would re-render the form, execute that OnLoad function and this can submit my form, but I'm trying to avoid reloading the form, I want the buttons to work asynchronously, so there will be no reload and any OnLoad events there would not fire.