Question

C#: Does Serializable() attribute prevent passing a class instance to another form?

I have the following classes, and is trying to build a settings module for my application. But when i try to access _configurator in settingForm method i get an exception: “object reference not set to an instance of an object”. Why?

[Serializable()]
public class Config
{
    public Config() { }
    public string ComPort
    {
        get
        {
            return comPort;
        }
        set
        {
            comPort = value;
        }
    }

    private string comPort;

}

public partial class kineticMoldDockUserControl : UserControl
{

    private settingsForm setForm = null; 

    private Config _cf = null;



    public kineticMoldDockUserControl()
    {
        InitializeComponent();

        _cf = new Config();
        _cf.ComPort = "COM12";

    }




    private void preferencesToolStripMenuItem_Click(object sender, EventArgs e)
    {



        if (!Application.OpenForms.OfType<settingsForm>().Any())
        {

            setForm = new settingsForm();

            setForm.Show();

            setForm.cf = _cf;


        }



    }


}

public partial class settingsForm : Form
{

    Config _configutor = null;
    public Config cf { get { return _configutor; } set { _configutor = value; } }


    public settingsForm()
    {
        InitializeComponent();

        try
        {
            MessageBox.Show(_configutor.ComPort.GetType().ToString());
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }

     }

}

Answer 1

You error has no relation with Serializable attribute. Problem lies in below lines of code:

            setForm = new settingsForm();

            setForm.Show();

            setForm.cf = _cf;

SettingsForm constructor is using configurator but you are setting it after constructor is called. You may pass the configurator via constructor to solve your issue.