Create a delegate from methodinfo

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I have the following Situation :

VB

Dim myType As Type = Repeat_Tastendruck_Control.GetType
 Dim myInfo As System.Reflection.MethodInfo = myType.GetMethod("OnClick", Reflection.BindingFlags.NonPublic Or Reflection.BindingFlags.Instance)

 If myInfo IsNot Nothing Then
      Dim myDelegate As delegate_OnClick = [Delegate].CreateDelegate(GetType(delegate_OnClick), myInfo, False)
     'Repeat_Tastendruck_Control.Invoke(myDelegate, Nothing)
     myDelegate(EventArgs.Empty)
     Exit Sub
 End If

I get in myType the Type of Repeat_Tastendruck_Control
I get in myInfo the the required MethodInfo
If I now create a Delegate to call this Method it points to a not instanced object. So ... where is my mistake ?
Any guidance would be usefull ... ;)

Additional Information :

the definition of the OnClick-Method :

VB

Protected Overrides Sub OnClick(e As System.EventArgs)
    MyBase.OnClick(e)
End Sub

the definition of the delegate :

VB

Private Delegate Sub delegate_OnClick(e As EventArgs)

the command "myDelegate(EventArgs.Empty)" calls the right in method - but not in the Control which is referenced by "Repeat_Tastendruck_Control".

What I have tried:

..................................

Posted 5-Sep-16 0:03am

Ralf Meier

Updated 5-Sep-16 9:33am

v2

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Richard Deeming 5-Sep-16 9:58am

What's the definition of the OnClick method, and the delegate_OnClick delegate?

Ralf Meier 5-Sep-16 14:32pm

Thanks for your reply, Richard. I have updated/improved my question.

Ralf Meier 23-Mar-17 7:38am

Hi Richard,
I'm sorry but I must ask you once more to this question.
For your Information : the code you gave me works well until now - with one exeption (and this is my additional question to it) :

When I work with a Control where I have overrided the Method "OnClick" it works.
But when I work with a Control which give this method (I think it comes from the Protected-attribute) I can't get a Delegate - but the MethodInfo is correct and the same like the MethodInfo from my derived Control.

Could you please point me again ...?

Richard Deeming 23-Mar-17 7:50am

Probably best to post this as a new question, with an example of the code you're using.

Ralf Meier 23-Mar-17 8:01am

OK ... I will do my very best ... ;-)

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Richard Deeming · Accepted Answer · 2016-09-05T09:33:00

When you create a delegate pointing to an instance method, you have to provide the "Me" object which will be used when the delegate is invoked. Because you haven't done that, and you've specified False for the throwOnBindFailure parameter, your delegate instance will be set to Nothing.

There are two ways you can solve this:

1. To create a delegate bound to a single instance of the class, use one of the CreateDelegate overloads which accept a firstArgument parameter:

VB.NET

Dim myDelegate As delegate_OnClick = [Delegate].CreateDelegate(
    GetType(delegate_OnClick),  ' The delegate type
    Repeat_Tastendruck_Control, ' The object instance - "Me"
    myInfo)                     ' The method info

myDelegate(EventArgs.Empty)

Delegate.CreateDelegate Method (Type, Object, MethodInfo) (System)[^]

2. To create a delegate which can be reused with multiple instances of the class, give your delegate an extra parameter to represent the object instance: