I need to pass a reference of a function to another function in VB.NET. How can this be done?
My function needs to use AddHandler internally, for which I need to pass it a handling function. My code below obviously does not work, but it conveys the idea of what I need.
Public Function CreateMenuItem(ByVal Name As String, ByRef Func As AddressOf ) As MenuItem
Dim item As New MenuItem
item.Name = Name
'item. other options
AddHandler item.Click, AddressOf Func
Return item
End Function
Is there another way to do this? The AddHandler needs to be set to a passed parameter in a function somehow...
A function delegate is just what you need to do this. First you need to define the delegate somewhere in the class. Change the signature to fit your event of course.
Public Delegate Sub MyDelegate(sender As System.Object, e As System.EventArgs)
Your function will take the delegate as an argument.
Public Function CreateMenuItem(ByVal Name As String, del As MyDelegate) As MenuItem
''''
AddHandler item.Click, del
''''
End Function
Public Sub MyEventHandler(sender As System.Object, e As System.EventArgs)
''''
End Sub
And here's how you call the function:
CreateMenuItem(myString, AddressOf MyEventHandler)