Transfer datafrom one form to an other

Question

I have a C# application with two forms(form1,form2).In form1 on btnTransfer_click I open second form.

private void btnTransfer_Click(object sender, EventArgs e)
{
    Form2 frmConn = new Form2 ;
    frmConn .Show();

    //i need here values from second form 

}

In second form I have 2 textboxes (txtUser,txtPassword) and a button (btnOk) .On button btnOk I verify user and password and if are correct i have to come back to first form and get this values on click button.

In Form2 :

private void btnOk_Click(object sender, EventArgs e)
{
      //verify if txtUser and txtPassword are correct 
    //if are corrects i have to send back to first form
    this.Close();
}

How can I do This? Thanks!

Answer 1

In the class for form2, create two public class properties, one for the value of each textbox:

private String _username = null;
public String UserName { get { return _username; } }
private String _password = null;
public String Password { get { return _password; } }

In form2 you can verify and assign to properties:

private void btnOk_Click(Object sender, EventArgs e)
{
    //verify if txtUser and txtPassword are correct

    if (correct)
    {
        _username = txtUser.Text;
        _password = txtPassword.Text;
    }
    this.Close();
}

Then you can retrieve them in your form1 code as such:

private void btnTransfer_Click(Object sender, EventArgs e)
{
    //This using statement will ensure that you still have an object reference when you return from form2...
    using (Form2 frmConn = new Form2())
    {
        frmConn.Show();

        String user = frmConn.UserName;
        String pass = frmConn.Password;

        if (!String.IsNullOrEmpty(user) && !String.IsNullOrEmpty(pass))
            //do something with them, they are valid!
    }
}

Answer 2

Usually, it's using a Data Transfer Object:

http://msdn.microsoft.com/en-us/library/ff649585.aspx

Or a Domain Object.

http://msdn.microsoft.com/en-us/magazine/dd419654.aspx