Adding user controls at runtime using string

[APaule]

Thanks to everyone again you are brilliant.

davearia is right. You are all brilliant, and even though self-praise stinks, I am brilliant too :D , BECAUSE: What puzzled me all the time (beside the solution for davearia) was the question, how to create random controls out of the types of the System.Windows.Forms namespace that come similar to davearia's question, for instance out of a table? So all you have is strings. And possibly with Option Strict On. And here is what I elaborated (if sombody is interested), owing to all the hints above:

		Dim Asm As [Assembly]
	Dim vType As Type
	Dim Ctrl As Control

	Asm = [Assembly].LoadWithPartialName("System.Windows.Forms")
	vType = Asm.GetType("System.Windows.Forms.TextBox")
	Ctrl = CType(Activator.CreateInstance(vType), Control)
	Ctrl.Name = "myTextBox"
	Me.Controls.Add(Ctrl)

The one and only question left is, how to add an eventhandler to a control, without hardcoding the delegates. I found no method in the reflection namespace that returns an object that could be casted into an eventhandler. But maybe sombody else knows and let us know.

 

I'd appreciate it. :)

[snarfblam]

There is System.Reflection.EventInfo class. The System.Type class has a method, GetEvents(), which returns an array of EventInfo objects representing each of a certain type's events. How to handle these events without a preexisting delegate is beyond me.

[AlexCode]

To add the event handler like you want:

 

               Dim asm As System.Reflection.Assembly
               't = Type of the object where the event handler procedure is
               'You can use the referenced assembly to get this type: t = asm.GetType("Calss...path")
               Dim t As Type

               Dim c As System.Windows.Forms.Control   'Control reflected

               Dim mymethod As System.Reflection.MethodInfo = t.GetMethod("Procedure Name")
               Dim pEv As System.Reflection.EventInfo = Me.GetType.GetEvent("Click")
               Dim pDel As [Delegate] = [Delegate].CreateDelegate(pEv.EventHandlerType, mymethod)
               pEv.AddEventHandler(c, pDel)

 

Alex :p

[APaule]

Hey, thats cool, thanks a lot. :) :) :)

 

But there are two minor questions left.

 

1.)

Dim mymethod As System.Reflection.MethodInfo = t.GetMethod("BClick")

This only detects public methods. Even when I extended the line to

t.GetMethod("BClick", BindingFlags.NonPublic)

it returned nothing. The method had to be public.

 

2.)

Dim pDel As [Delegate] = [Delegate].CreateDelegate(pEv.EventHandlerType, mymethod)

At that line an exception was thrown. The method has to be static.

 

Ok, 2.) is not a question; I can live with that, though it might have implications with declaration of variables used in that method, but 1.) is strange. Am I doing something wrong, or is it a bug?

[APaule]

Just found out something: When you extend the line to

t.GetMethod("BClick", BindingFlags.NonPublic Or BindingFlags.Static)

it also works with private methods - but only if it's static as well.

 

It's really strange that this methods doesn't return any method that is just private. It HAS to be declared private shared. In this case it doen't matter, because the CreateDelegate methods needs a static one, but in other cases....

 

Any idea?