How can I get a click event from a control object

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Hello to everyone, How are you?
Have a great day.

I'm trying to code a Web Solution to add some WebUserControls dinamically and cacht their Click Event. I read some forums like this and I found out that for that it was necesary to Delegate my click event from my Control and reasign thru AddHandler and AddressOf instructions on my "Default.aspx" file.

Well, to this step everything goes fine. But when I click any button from my Control I got a System.InvalidCastException Error Message (HResult=0x80004002) that says that is not possible convert a "System.Web.UI.HtmlControls.HtmlGenericControlobject" Object Type to "MyControl" Object.

It makes reference to an especific instrucction on my click event from my "Default.aspx" file:

Dim laFiguraSeleccioanda As MiControl = DirectCast(DirectCast(sender, Button).Parent, MiControl)

And that is a call from my click event from My Control file with this instrucction:

RaiseEvent EventoPublico_Click(sender, e)

Can some one please help me? How can I catch click event from MyControl file and I do something declarated on my Default page?

I let all of you my code built on ASPX.VB so you can have a better idea what I mean.

Here is a Screen Shot ---> ScreenShot

Wishing you all an excellent day, I reiterate my greeting and thank you in advance for your kind attention and help.

What I have tried:

Default.aspx

ASP.NET

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<%@ Register Src="~/App_Controls/MiControl.ascx" TagPrefix="CJS" TagName="Figura" %>
<head runat="server">
    <title>Evento click con delegado</title>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <link href="StyleSheet.css" type="text/css" rel="stylesheet" />
</head>
<body>
    <form id="form1" runat="server">
        <div runat="server">
            <asp:PlaceHolder ID="PlaceHolder1" runat="server"></asp:PlaceHolder>
        </div>
        <br />
        <div runat="server" class="Texto" style="clear:left">
            <asp:Label ID="lbResultado" runat="server" Text="Esperando un Click.."></asp:Label>
        </div>
    </form>
</body>

Default.aspx.vb

HTML

Partial Class _Default
    Inherits System.Web.UI.Page
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles form1.Load
        For i As Integer = 1 To 3
            Dim laFigura As MiControl = LoadControl("~/App_Controls/MiControl.ascx")
            AddHandler laFigura.EventoPublico_Click, AddressOf LaFigura_Click
            PlaceHolder1.Controls.Add(laFigura)
            laFigura.SuNombre = "Cuadrito 0" & i
        Next
    End Sub

    Protected Sub LaFigura_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim laFiguraSeleccioanda As MiControl = DirectCast(DirectCast(sender, Button).Parent, MiControl)
        lbResultado.Text = "Hiciste click en el " & laFiguraSeleccioanda.SuNombre
    End Sub
End Class

MiControl.ascx

ASP.NET

<%@ Control Language="VB" AutoEventWireup="false" CodeFile="MiControl.ascx.vb" Inherits="MiControl" %>
<link href="../StyleSheet.css" type="text/css" rel="stylesheet" />
<asp:Panel ID="Cuadrito" CssClass="Cuadrito Centro" runat="server">
    <div runat="server">
        <asp:Label ID="lbCuadrito" CssClass="Texto" Text="Control" runat="server" ></asp:Label>
    </div>
    <div runat="server">
        <asp:Button ID="btnCuadrito" runat="server" Text="Haz click" />
    </div>    
</asp:Panel>

MiControl.ascx.vb

HTML

Partial Class MiControl
    Inherits System.Web.UI.UserControl

    Public Delegate Sub Delegado_EventoClick(ByVal sender As Object, ByVal e As System.EventArgs)
    Public Event EventoPublico_Click As Delegado_EventoClick
    Public Property SuNombre As String
        Get
            Return lbCuadrito.Text
        End Get
        Set(value As String)
            lbCuadrito.Text = value
        End Set
    End Property
    Private Sub btnCuadrito_Click(sender As Object, e As EventArgs) Handles btnCuadrito.Click
        RaiseEvent EventoPublico_Click(sender, e)
    End Sub

End Class

Error Message:

System.InvalidCastException occurred
  HResult=0x80004002
  Message=No se puede convertir un objeto de tipo 'System.Web.UI.HtmlControls.HtmlGenericControl' al tipo 'MiControl'.
  Source=App_Web_tumekcyd
  StackTrace:
   at _Default.LaFigura_Click(Object sender, EventArgs e) in D:\Mis documentos\Ejemplo 03 - Evento Click con delegado\Default.aspx.vb:line 14
   at MiControl.btnCuadrito_Click(Object sender, EventArgs e) in D:\Mis documentos\Ejemplo 03 - Evento Click con delegado\App_Controls\MiControl.ascx.vb:line 16

Posted 15-Jan-18 4:34am

Cuijos

Updated 16-Jan-18 6:09am

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Richard Deeming · Accepted Answer · 2018-01-16T06:09:00

The button's parent is the <div>, not the user control.

You could either use the button's NamingContainer:

Dim laFiguraSeleccioanda As MiControl = DirectCast(DirectCast(sender, Control).NamingContainer, MiControl)

Or, you could modify the code which raises the event so that it passes the correct sender:

Private Sub btnCuadrito_Click(sender As Object, e As EventArgs) Handles btnCuadrito.Click
    RaiseEvent EventoPublico_Click(Me, e)
End Sub

which would simplify the handler:

Dim laFiguraSeleccioanda As MiControl = DirectCast(sender, MiControl)