passing values between forms (winforms)

  • pf.ShowDialog(this); is a blocking call, so pf.Submit += new ParameterForm.ParameterSubmitResult(pf_Submit); is never reached: switch the order.

  • Submit(this,this.node); throws a null object reference because no event is assigned to it (see above). Generally, you should always check first: if (Submit != null) Submit(this,this.node);

  • You should change ``pf.ShowDialog(this);topf.Show(this);` so that your main form isn't disabled while your dialog box is open, if that's what you want, or use the model below (typical for dialog boxes.)


I'm not sure what pf_Submit is supposed to do, so this might not be the best way to go about it in your application, but it's how general "Proceed? Yes/No" questions work.

Button ParametersButton = new Button();
ParametersButton.Click += delegate
    {
        ParameterForm pf = new ParameterForm(testString);
        pf.ShowDialog(this); // Blocks until user submits
        // Do whatever pf_Submit did here.
    };

public partial class ParameterForm : Form
{
    public string test;     // Generally, encapsulate these
    public XmlElement node; // in properties

    public void SubmitButton_Click(object sender, EventArgs e)
    {
        Debug.WriteLine(test);
        this.Close(); // Returns from ShowDialog()
    }
 }