runtime change into database

[C# Programming]

i have four radiobutton and a button.first i m selecting item through radiobutton and adding items into textbox on button click_event.now i want that item which are shown in textbox can be edited and reflect back into database.
here main problem is i hav four txtbox which is populated by different database table and table is selected on radio_click event.but i m unable to made the changes into database when user deleted textbox data.