VB.NET OnClientClick javascript server side

Here is the scenario:

I have a aspx page that displays Table with few data columns driven by database and an additional column which displays a dynamically created "Delete" button. This button is created at run time in the server side code (vb.net). When the user clicks this delete button, i want to display a confirmation message.

Solution:
1. Define the following javascript function within aspx page:


<script type = "text/javascript">
        function ConfirmDeleteClient() {
            var confirm_output = document.createElement("INPUT");
            confirm_output.type = "hidden";
            confirm_output.name = "confirm_output";
            if (confirm("Are you sure you want to delete this item?")) {
                confirm_output.value = "Yes";
            } else {
                confirm_output.value = "No";
            }
            document.forms[0].appendChild(confirm_output);
        }
    </script>

2. Code for creating the "delete" button dynamically in Page_load():

    btnDelete.Text = "Delete"
     btnDelete.ID = sqlRead("record_id").ToString()
     btnDelete.PostBackUrl = "~/xxx.aspx"
     AddHandler btnDelete.Click, AddressOf btnDelete_Click                
     btnDelete.OnClientClick = "ConfirmDeleteClient()"

3. Click handler:


 Protected Sub btnDelete_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim btn As Button = CType(sender, Button)    
        Try
            Dim confirmValue As String = Request.Form("confirm_output")
            If confirmValue = "Yes" Then
                'Whatever action you want to take                
            End If
            'result = MsgBox("Are you sure you want to delete this letter?", MsgBoxStyle.ApplicationModal + MsgBoxStyle.YesNo, "Please confirm")
        Catch ex As Exception
            logger.Error(ex)
        End Try
    End Sub