late binding

[Andy]

I don't fully understand the concept of late and early binding. I recently started using option strict and my code fell apart arrgh!

I fixed all of my errors except four of them and here is a sample of what I have left:

Private Sub tab_25_btnClearAll_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
    Handles tab_25_btnClearAll.Click
        'Purpose : Clears the CU tabpage
 
        Try
            Client.ClearTab(sender.parent)
            tab_25_optNo.Checked = True
 
        Catch ex As Exception
            ErrorMessage(ex.Message)
 
        End Try
    End Sub

the error is "option strict disallows late binding' and it highlights the "sender.parent" section. what can I do to correct this?

[nemaroller]

Late-binding means the runtime must examine the generic object and try to coerce into the receiving container.

Early-Binding refers to explicity informing the compiler of what type of object the sender is, and what type of object the receiver is, so it can compile your app at build-time into the appropriate instructions, saving a whole hell lot of work for the runtime.

For your code, ask yourself, who is the Sender? Assume for example it was a TabPage.

'late-binding, compiler only knows Sender is an object (object has no property .parent)
'with option strict off, it includes code instructing
'runtime to call a "parent" method when it runs
Client.ClearTab(sender.parent)
 
'compiler now has instructions from you to cast the sender
'into a TabPage....which the compiler knows has a "parent" method
Client.ClearTab(DirectCast(Sender, TabPage).parent)

[taxes]

Hi,

You need to put a CType in there somewhere. I'm not familiar with your paticular construction but the following is an excerpt from code I use

Dim intcount As Object
        For Each intcount In Controls
 
            If TypeOf intcount Is CheckBox Then
                CType(intcount, CheckBox).Checked = True
 
 
            End If
        Next