Over on the develomentor advanced-dotnet mailing list Frans Bouma recently posted an answer to the question: How do you perform an operation the first time a control is added to the form.
Considering the Design time stuff is something I need to learn more about I thought I’d post his answer here in case I need to do something like that in the future (not to mention help whoever may read this)
Though I’d use a Toolbox item
Create a simple class derived from System.Drawing.Design.ToolboxItem and add it to your control via the ToolboxItemAttribute, which takes a string or a typeof definition.
In your ToolboxItem class, you override CreateComponentsCore and you there create your control and also do your things you want to execute when the control is placed onto the form.