If you have two or more forms, you need an object to store the information, since when you move from one form to another, you are instantiating a new form (In other words, you start again), therefore you can follow this example.
Structure of the person (DTO):
public class Persona
{
public string Nombre {get; set;}
public Persona(){}
}
Main Form, which starts the application
public class FormularioPrincipal
{
public Persona Persona = null;
public void AbrirFormulario2()
{
Persona persona = new Persona();
Persona = persona;
FormularioPersona form = new FormularioPersona(ref persona);
this.Hide();
form.Show();
}
}
Form which fills all the information of the person (Vista)
public class FormularioPersona
{
public Persona Persona = null;
/*Constructor del formulario, la cual hace referencia al objeto persona del formulario principal*/
public FormularioPersona (ref persona)
{
Persona = persona;
}
/*Método para completar la informacción de una persona*/
public void CompletarInformacionPersona()
{
Persona.Nombre = textbox.Text;
this.Close();
}
}
Greetings, I hope I have helped you.