Delegates and events:

Delegates and events:

Handle or Subscribe to ASP.NET Controls events from UserControl in ASPX Page.

Step 1:

Create a usercontrol having a textbox and button control

Search Catalogue by Points <br><br>

<asp:Panel ID="Panel1" runat="server" DefaultButton="btnSubmit">

<input type="text" name="Text1" size="4" maxlength="6" ID="Text1" runat="server"/>

<asp:Button ID="btnSubmit" runat="server" Text="Go"

OnClientClick="javascript:return clickherego(this.form);"

style="color:White;background-color:#75bde9;border-style:None;width:25px;height:20px;font-size:10px;font-family:verdana"

onclick="btnSubmit_Click"/> </asp:Panel>

Explanation:

DefaultButton="btnSubmit" in panel control will trigger btnSubmit button click when user presses enter key or return key in Mac.

Step 2:

Inherit EventArgs Class to Pass values to Event Handler. This will enable us to get the user control textbox values in ASPX page.

public class NavEventArgs : EventArgs

{

private int _text;

public int SearchText

{

get { return _text; }

}

public NavEventArgs(int searchtext)

{

this._text = searchtext;

}

}

Step 3:

Create an event in UserControl1.ascx.cs file

private bool _goClicked;

public bool GoClicked

{

get { return _goClicked; }

set { _goClicked = value; }

}

private int _text1value;

public int Text1Value

{

get { return _text1value; }

set { _text1value = value; }

}

public delegate void NavEventHandler(object sender, NavEventArgs e );

public event NavEventHandler GoButtonClicked;

Step 4:

Fire the GoButtonClicked event in submit button clicked event.

protected void btnSubmit_Click(object sender, EventArgs e)

{

GoClicked = true;

Text1Value = Convert.ToInt32(Text1.Value);

Text1.Value = string.Empty;

if (GoButtonClicked != null)

{

//this value can be accessed using e.SearchText in EventHandler

NavEventArgs e1 = new NavEventArgs(Text1Value);

//Fire the event

GoButtonClicked(this, e1);

}

}

Entire UserControl1.ascx.cs file

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

public partial class dinning_navigation : System.Web.UI.UserControl

{

private bool _goClicked;

public bool GoClicked

{

get { return _goClicked; }

set { _goClicked = value; }

}

private int _text1value;

public int Text1Value

{

get { return _text1value; }

set { _text1value = value; }

}

public delegate void NavEventHandler(object sender, NavEventArgs e );

public event NavEventHandler GoButtonClicked;

protected void Page_Load(object sender, EventArgs e)

{

GoClicked = false;

Text1.Attributes.Add("onkeydown", "if(event.keyCode== 13){document.getElementById('" + btnSubmit.UniqueID + "').click();}");

}

protected void btnSubmit_Click(object sender, EventArgs e)

{

//Response.Redirect("search_result.aspx?text=" + Text1.Value);

GoClicked = true;

Text1Value = Convert.ToInt32(Text1.Value);

Text1.Value = string.Empty;

if (GoButtonClicked != null)

{

NavEventArgs e1 = new NavEventArgs(Text1Value);

GoButtonClicked(this, e1);

}

}

}

public class NavEventArgs : EventArgs

{

private int _text;

public int SearchText

{

get { return _text; }

}

public NavEventArgs(int searchtext)

{

this._text = searchtext;

}

}

Step 5:

Handle GoButtonClicked event in ASPX

Step 5.1:

Add the user control to EventsTest.aspx page

<%@ Register Src="dinning_navigation.ascx" TagName="dinning_navigation" TagPrefix="uc1" %>

<uc1:dinning_navigation ID="Dinning_navigation1" runat="server" OnGoButtonClicked="dinning_navigation_GoButtonClicked" />

Step 5.2:

Event Handler for GoButtonClicked. Now OnGoButtonClicked event will automatically showed by Intellisense in visual studio. dinning_navigation_GoButtonClicked is the EventHandler name I have given.

OnGoButtonClicked="dinning_navigation_GoButtonClicked"

Step 5.3:

EventHandler for GoButtonClicked event in EventsTest.aspx.cs file.

protected void dinning_navigation_GoButtonClicked(object sender, NavEventArgs e)

{

FillGrid4GoButtonClicked(e.SearchText);

GridView1.PageIndex = 0;

GridView1.DataBind();

}