c# - C# Web Browser: get contents of input texts when user submits form

Question

I have a Web Browser control on my C# application. I would like to get the value the user inputs in the text input of the form when he clicks the submit button (or changes the page).

I know I can use:

webBrowser1.Document.GetElementById("inputA").InnerText

To get the value of the input tag.

My question is, how can I detect the submit event so that I can store this value into a string?