How to put an extended WinForms Control on ToolBox

Question

I plan to add functionalities to TextBox with the following:

   public class TextBoxExt : TextBox  
    {
        protected override void OnKeyPress(KeyPress         


        

Answer 1

I created an empty constructor for my custom implementation of UltraGridBagLayoutPanel. Although david.healed is right it isn't necessary, it is quite useful to put a breakpoint in to check that when the form initialises it is using your class to implement your custom control.

It would have been a lot easier to edit the designer file, but I tried it and changed both the field type for the control and also changed the assignment of the field to a new instance of my custom control.

private Infragistics.Win.Misc.UltraGridBagLayoutPanel ultraGridBagLayoutPanel1;
this.ultraGridBagLayoutPanel1 = new Infragistics.Win.Misc.UltraGridBagLayoutPanel();

to

private Athia.Reports.ultraGridBagLayoutPanel1 ultraGridBagLayoutPanel1;
this.ultraGridBagLayoutPanel1 = new Athia.Reports.ultraGridBagLayoutPanel1();

Doing this destroys Visual Studio every time, and to fix it requires using a text editor to put it back again. Therefore unless anyone can describe what is wrong with my implementation of this approach, perhaps calling the class the same as the control name isn't a great idea, I think the only safe and reliable way to achieve this is as Calanus describes in steps 1 to 5 or as an small deviation from that as Rob Windsor rightly points out restarting VS will bring the control into the Toolbox automatically. Unfortunately for me I then have to change all of the child controls over from the original class to my customised class :-(.

Answer 2

You need to add a constructor to your derived class.

public class TextBoxExt : TextBox      
{        
    public TextBoxExt()
    {
    }

    protected override void OnKeyPress(KeyPressEventArgs e)        
    {            
         base.OnKeyPress(e);        
    }    
}

Answer 3

I fell into this trap just a couple of hours ago.
I've got a .NET 2.0 Windows Application project with some custom UserControls; it worked fine. So I decided to order my files in subfolders, to make my project a little bit cleaner.
After that, Visual Studio 2010 designer stopped loading my forms, and ToolBox won't show my controls anymore.
I freaked out, moving back source files in project root, resetting ToolBox, but nothing seemed to work. After that, I remembered I used ReSharper "Remove Unused References", so I tried to put back unused reference, in particular System.Data: problem solved! :O
I can't say you why, but this worked for me.
Hope my experience can help someone else. :)
Bye, Nando

Answer 4

Your control should appear in the toolbox for your solution automatically. To have it appear for other projects, you have to do Choose Toolbox items, as others have said.

If you want to provide special design-time functionality, then you will also need to provide some additional designer related attributes and probably your own class derived from ControlDesigner.

Answer 5

Any custom control in your project should show up in the Toolbox automatically. I have found that sometimes the controls won't show until you close a re-open Visual Studio. I assume the issue has something to do with caching of the contents of the Toolbox.

Answer 6

I know this is super old question, but maybe still useful for someone else that has same problem like me - as it's still on the top Google :)

You might interest to use ToolboxItemAttribute (http://msdn.microsoft.com/en-us/library/system.componentmodel.toolboxitemattribute(v=vs.110).aspx).

I did this at my end to resolve the problem.

[ToolboxItem(true)]
public class PanelTitle : LabelControl  {
   // Whatever code to override LabelControl here...
}

Rebuild the solution and the extended control should be shown in the toolbox.