Send parameter to addhandler?

Question

I have a button in a grid that I created programmatically. The button edits some data in a table using data in a hidden column of the grid that the button is in. Normally I send a hidden field the row data using javascript onclientclick of the button then make the changes to the database using that hidden field. But there must be a way to send the addhandler of the button a parameter. This is the code i have to clarify....

Dim btnedit As New ImageButton
    AddHandler btnedit.Click, AddressOf btnedit_Click
    btnedit.ImageUrl = "\images\bttnEditMini.gif"

If e.Row.RowType <> DataControlRowType.Header And e.Row.RowType <> DataControlRowType.Footer Then
        e.Row.Cells(3).Controls.Add(btnedit)
End If

here is my Addhandler with its delegate:

Public Delegate Sub ImageClickEventHandler(ByVal sender As Object, ByVal e As ImageClickEventArgs)
Sub btnedit_Click(ByVal sender As Object, ByVal e As ImageClickEventArgs)
//programming stuff
End Sub

How can i send this handler a parameter?

Answer 1

Since it was in a grid i just used the row command instead. And when Row command is used you can send it a commandname and a commandargument. I passed my parameter as the argument.

 GridView1.Rows(i).Cells(3).Controls.Add(btndel)
            btndel.ImageUrl = "\images\bttnDelete.gif"
            btndel.ToolTip = "This will delete the Selected Assignment"
            btndel.CommandName = "destroy"
            btndel.CommandArgument = GridView1.Rows(i).Cells(0).Text
            btndel.Attributes.Add("onclick", "javascript: if(confirm('Are you sure you want to delete this Department Cost Days Assignment?')==false) return false;")

here is the rowcommand:

Protected Sub GridView1_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView1.RowCommand
    If e.CommandName = "destroy" Then 'used destroy because Delete command was prohibited.
       Call Connection()
        Dbcmd.CommandText = "Delete from table where condition = '" & e.CommandArgument & "'"
        Dbcmd.ExecuteNonQuery()
        Dbconn.Close()
        Dbconn.Dispose()
    End If

Answer 2

By convention, all event handlers accept two parameters: the sender, and the EventArgs. If you need to send custom information to the listeners, create a new class that inherits from EventArgs and contains the information that you need to communicate.

Check out this article on CodeProject that shows you how to do this.

Answer 3

Short answer: no. Where would you send it? You've got two parameters.

Longer answer: sender is the control that sent the event. In this case, it will be your btnEdit control. Maybe that will help you.

Answer 4

If you don't want to use the 'default'/already defined parameters, you can create your own events.