Posts tagged EventHandler

In this post, we want to show how button in user control communicate with web page in asp.net

First create user control called button.ascx.

Add 3 button, name it btnSave, btnEdit and btnCancel.

in button.ascx back code, add this code:

Public Partial Class button
    Inherits System.Web.UI.UserControl
    Public Event btnSaveHandler As System.EventHandler
    Public Event btnEditHandler As System.EventHandler
    Public Event btnCancelHandler As System.EventHandler

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub

    Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnSave.Click
        RaiseEvent btnSaveHandler(Me, New EventArgs())
    End Sub

    Protected Sub btnEdit_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnEdit.Click
        RaiseEvent btnEditHandler(Me, New EventArgs())
    End Sub

    Protected Sub btnCancel_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnCancel.Click
        RaiseEvent btnCancelHandler(Me, New EventArgs())
    End Sub
End Class

In Default.aspx, add 1 label called label1, then drag the button.ascx to the default.aspx.
Add code in default.aspx as below:

Partial Public Class _Default
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Label1.Text = Request.QueryString("label")
        AddHandler button1.btnCancelHandler, AddressOf cancelClick
        AddHandler button1.btnEditHandler, AddressOf editClick
        AddHandler button1.btnSaveHandler, AddressOf saveClick
    End Sub

    Private Sub cancelClick(ByVal sender As Object, ByVal e As EventArgs)
        Response.Redirect("default.aspx?label=Cancel")
    End Sub

    Private Sub editClick(ByVal sender As Object, ByVal e As EventArgs)
        Response.Redirect("default.aspx?label=Edit")
    End Sub

    Private Sub saveClick(ByVal sender As Object, ByVal e As EventArgs)
        Response.Redirect("default.aspx?label=Save")
    End Sub
End Class

Run it, you will see that button that we create in user control can be manipulate and used in default.aspx
See other example for communication between user control and page in:
http://www.codeproject.com/KB/user-controls/Page_UserControl.aspx