An exception thrown that I can't figure out how to fix

[DaveyM69]

Ditto the comments from the others. Probably the most correct way to acheive the result that the tutorial was aiming for would be to: 1. Create a Case enum. 2. Have a private field of type Case in the dialog form that is set according to the radio buttons and expose this field in a public read only property. 3. Check the DialogResult of the dialog form in the main form, if OK then read the property before disposing of the form. 4. Use the Case obtained from the property in a switch block and change the TextBox's Text property accordingly. What is it you were wanting to learn from that tutorial - changing the case of a string, using a dialog to get a user selection that may be returned to the instanciating form, or general inter-object communication?

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Why are you using VB6? Do you hate yourself? (Christian Graus)

[AspDotNetDev]

Luc Pattyn wrote:

Trying to learn from a free site only gives you what you paid for, i.e. nothing much.

I don't know, I can think of at least one site that is free and is a pretty good learning resource. It may not compare to a book, but it is a little more than "nothing much". :rolleyes:

[Forum Guidelines]

[Luc Pattyn]

that must be an exceptional site then. :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

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I only read code that is properly formatted, adding PRE tags is the easiest way to obtain that.
[The QA section does it automatically now, I hope we soon get it on regular forums as well]

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[Darrall]

Thanks Dave. Basically the idea was to introduce using multiforms with the second form used to perform the changes on the first form. As you have all pointed out I am obviously using a poor source of information.

[DaveyM69]

I'll knock you up a simple demo this weekend and post back here if that would be helpful. Colin Mackay has an article here[^] about passing data between forms. It's .NET 1.1 IIRC but the principles are still valid :thumbsup: In this situation, you only need the simpler Parent to Child relationship as that method can be used for both writing to and reading from properties. The Child to Parent is only needed when the Child needs to inform the parent when something has changed.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Why are you using VB6? Do you hate yourself? (Christian Graus)

[Darrall]

Thanks Dave...I'd appreciate that. You are the first one that has given me any kind of answer. I know the tutorial I am using is crappy but I'd still like to solve this particular problem. Thanks again. Darrall

[DaveyM69]

OK, this does the same as the tutorial but it does it correctly. I have included an example of both Parent to Child (Parent reads a property in the child) and Child to Parent (Parent listens for event that the Child raises). For a beginners tutorial to events, have a look at my Events Made Simple article[^]. Anyway, here's the code - any questions, just ask! I've included all the control creation and initialization so you can copy and paste and it should work without having to add any controls in the designer.

// Case.cs
public enum Case
{
None,
Upper,
Lower,
Proper
}

// FormChild.cs
using System;
using System.Drawing;
using System.Windows.Forms;

public partial class FormChild : Form
{
#region Events

public event EventHandler SelectedCaseChanged;

#endregion

#region Fields

private Case selectedCase;

/\* Would normally be in the Designer.cs file \*/
private RadioButton radioUpper;
private RadioButton radioLower;
private RadioButton radioProper;
private Button buttonOK;
private Button buttonCancel;

#endregion

#region Constructors

public FormChild()
{
    InitializeComponent();
    CustomInitialize();

    selectedCase = Case.None;
    radioUpper.Tag = Case.Upper;
    radioLower.Tag = Case.Lower;
    radioProper.Tag = Case.Proper;
}

#endregion

#region Properties

/\* Public read only public property \*/
public Case SelectedCase
{
    get { return selectedCase; }
    private set
    {
        if (selectedCase != value)
        {
            selectedCase = value;
            OnSelectedCaseChanged(EventArgs.Empty);
        }
    }
}

#endregion

#region Methods

private void RadioButton\_CheckedChanged(object sender, EventArgs e)
{
    RadioButton selectedRadio = sender as RadioButton;
    if (sender != null)
        SelectedCase = (Case)selectedRadio.Tag;
}

protected virtual void OnSelectedCaseChanged(EventArgs e)
{
    EventHandler eh = SelectedCaseChanged;
    if (eh != null)
        eh(this, e);
}

/\* Creates all controls and sets properties
 \* Would normally be in the Deisgner.cs file \*/

[Darrall]

Thank you so much for your time and effort. I have spent all day at this and finally got it to work but yours looks much tidier. I will try it out tomorrow and let you know. Thanks again. Darrall

[DaveyM69]

No problem :-D In addition to my article I previously linked to, I have posted a Tip/Trick here[^] which is a little more concise and should help in understanding the basics of raising/handling events.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Why are you using VB6? Do you hate yourself? (Christian Graus)

[Darrall]

Thanks again :) With all your help I should come out on top...maybe