C# - Manually Fetch Values From Control?

I have a FormView control with Two text Boxes. Data source for the Controls is an ObjectDataSource

I want to fetch these values from both text boxes, create a User object and pass it to ObjectDataSource, which has an input method that accept a User object

I think I have to do it in

protected void ObjectDataSourceUsert_Inserting(object sender, ObjectDataSourceMethodEventArgs e)
{
// string _userName = FormViewUserDetails. ?
// string _password = FormViewUserDetails. ?
User user = new User {UserName = _userName, Password = _password};
e.InputParameters.Add(user);
}