Waghmare says:

AddHandler Me._btnNextStatus.Click, AddressOf Me._btnNextStatus

AddressOf operand must be the name of a method not the name of the button. 

Waghmare says:

If (Me._btnNextStatus IsNot Nothing) Then

                 Dim _showthumbsQC As showthumbsQC = Me

                 Me._btnNextStatus.remove_Click(New EventHandler(_showthumbsQC, _showthumbsQC.btnNextStatus_Click))

             End If

             Me._btnNextStatus = value

             If (Me._btnNextStatus IsNot Nothing) Then

                 Dim _showthumbsQC1 As showthumbsQC = Me

                 Me._btnNextStatus.add_Click(New EventHandler(_showthumbsQC1, _showthumbsQC1.btnNextStatus_Click))

 

                 AddHandler Me._btnNextStatus.Click, AddressOf Me._btnNextStatus

 

             End If

Both the condition is checking for IsNot Nothing.

So you can simplify as below.

Protected Overridable Property btnNextStatus As Button
    Get
        Return Me._btnNextStatus
    End Get
    <MethodImpl()>
    Set(ByVal value As Button)
        Dim _showthumbsQC As showthumbsQC = Me
        If (Me._btnNextStatus Is Nothing) Then
            Me._btnNextStatus = value
        End If
        AddHandler Me._btnNextStatus.Click, AddressOf _showthumbsQC.btnNextStatus_Click
    End Set
End Property

Thanks for your reply !!! It works.

for below line is it correct or not ?

MyBase.New()

Dim _showthumbsQC As showthumbsQC = Me

AddHandler MyBase.Init, AddressOf _showthumbsQC.Page_Init

existing line was below replaced with above line

' MyBase.add_Init(New EventHandler(_showthumbsQC, _showthumbsQC.Page_Init))

Yes its correct.

For dynamic handler refer below article.

Creating Dynamic Button LinkButton and ImageButton in ASP.Net