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aspx thread: code-behind for .ascx user controls
Message #1 by "Michael Gaertner" <mgaert@b...> on Thu, 4 Jan 2001 23:10:12 -0000
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Are there any examples out there of a simple code behind page that can be
inherited from a user control/.ascx. I'm trying to provide several user
controls with my DNS string from config.web and/or Context.Cache. Classes
inheriting from Page are no good for .ascx pages. Classes inheriting from
UserControl seem right, but I can't find anything about implementing the
HttpContext object correctly for class derived from UserCotrol.
Thanks.
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Message #2 by "Jacques Leclerc" <jleclerc2@h...> on Fri, 5 Jan 2001 07:40:31 -0500
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Here's the reply posted by Susan Warren (Microsoft) on a different
newsgroup.
*****************************
Beta1 of VS.NET does not support WYSIWYG editing of ASCX files, code-behind
or otherwise. (Sorry, we're working on this support but didn't get it in
for Beta1. It will be there in Beta2.) I can explain how to create and
consume a code-behind ASCX manually, however.
To create:
1. Make a new Web Form
2. optionally, do as much design as you wish using the WYSIWYG editor.
After the next two steps, you won't have this support.
3. close the file
4. rename to the .ASCX extension
5. reopen the .ASCX file and make these changes:
- Change the <%@ Page ... %> directive to <%@ Control ... %>
- remove the <html> tags, entire <head> section, <body> tags and
<form runat=server> tags (and their end tags)
6. open the code-behind class file (you'll need to Project > Show All Files
to see it) and make these changes:
- change System.Web.UI.Page to System.Web.UI.UserControl in the two
places it appears
- for C# classes only, change Page.Init to this.Init
To consume:
1. Add a Register directive to the page, pointing to the ASCX file (just
like a single file ASCX)
2. If you want to code against the user control in the codebehind class for
the ASPX page, you'll need to add an instance variable in the code behind.
For example, let's say I have a user control "mywidget.ascx" whose
code-behind class name is "mywidget", that I consume on WebForm1.aspx with
the id "m1". Further, the mywidget class defines a public member "message".
Here's how I'd set the message member programmatically:
Public Class WebForm2
Inherits System.Web.UI.Page
Protected m1 as mywidget
Sub Page_Load(sender as Object, e as EventArgs)
m1.message="Hello World"
End Sub
End Class
hth,
Susan
**********************************
"Michael Gaertner" <mgaert@b...> wrote in message
news:28945@a...
>
> Are there any examples out there of a simple code behind page that can be
> inherited from a user control/.ascx. I'm trying to provide several user
> controls with my DNS string from config.web and/or Context.Cache. Classes
> inheriting from Page are no good for .ascx pages. Classes inheriting from
> UserControl seem right, but I can't find anything about implementing the
> HttpContext object correctly for class derived from UserCotrol.
> Thanks.
>
---
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in-depth information for ASP developers everywhere.
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Message #3 by Susan Warren <swarren@m...> on Fri, 5 Jan 2001 09:36:06 -0800
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I think the other part of Michael's question is whether he can extend the
UserControl class (which is the base class for a user control) with some
functionality that will be shared across a number of user controls. The
answer is "sure", and it's a pretty powerful technique. It works for Pages
too! Say I always want to have my config-file-based DSN available to my
user controls. Here's how I'd make a derived class, and use it as the base
class for my user controls. (I show both code-behind and single file
versions below):
-----------------
Custom base class
-----------------
public class DataUserControl : UserControl {
public String MyDSN {
get {
return
(String)((Hashtable)Context.GetConfig("appsettings"))("dsn");
}
}
} //end class DataUserControl
--------------------------------------------------------
User Control that uses this base class: single file ASCX
--------------------------------------------------------
<%@ Inherits="DataUserControl" %>
<%@ Imports Namespace="System.Data" %>
<%@ Imports Namespace="System.Data.SQL" %>
<script language="C#" runat="server">
protected void Page_Load(object sender, EventArgs e) {
if (!IsPostBack) {
DataGrid1.DataSource
MyDatabaseMethod().Tables[0].DefaultView;
DataGrid1.DataBind();
}
}
DataSet MyDatabaseMethod() {
SQLConnection connection = new SQLConnection(MyDSN);
//MyDSN is set in the base class
SQLDataSetCommand command = new
SQLDataSetCommand("SELECT * FROM Products", connection);
DataSet dataset = new DataSet();
command.FillDataSet(dataset, "dataset");
return dataset;
}
</script>
<asp:DataGrid id=DataGrid1 runat="server" />
--------------------------------------------------------
User Control that uses this base class: ASCX/code-behind
--------------------------------------------------------
<%@ Control language="c#" Codebehind="UserControl1.cs"
Inherits="UserControl1" %>
<asp:DataGrid id=DataGrid1 runat="server" />
---------------------------------------------------------
User Control that uses this base class: code-behind class
---------------------------------------------------------
namespace r1cs
{
using System;
using System.Data;
using System.Data.SQL;
using System.Web.UI.WebControls;
public class UserControl1 : DataUserControl
{
protected DataGrid DataGrid1;
protected void Page_Load(object sender, EventArgs e) {
if (!IsPostBack) {
DataGrid1.DataSource
MyDatabaseMethod().Tables[0].DefaultView;
DataGrid1.DataBind();
}
}
DataSet MyDatabaseMethod() {
SQLConnection connection = new SQLConnection(MyDSN);
//MyDSN is set in the base class
SQLDataSetCommand command = new
SQLDataSetCommand("SELECT * FROM Products", connection);
DataSet dataset = new DataSet();
command.FillDataSet(dataset, "dataset");
return dataset;
}
}
}
hth,
Susan
-----Original Message-----
From: Jacques Leclerc [mailto:jleclerc2@h...]
Sent: Friday, January 05, 2001 4:41 AM
To: ASP+
Subject: [aspx] Re: code-behind for .ascx user controls
Here's the reply posted by Susan Warren (Microsoft) on a different
newsgroup.
*****************************
Beta1 of VS.NET does not support WYSIWYG editing of ASCX files, code-behind
or otherwise. (Sorry, we're working on this support but didn't get it in
for Beta1. It will be there in Beta2.) I can explain how to create and
consume a code-behind ASCX manually, however.
To create:
1. Make a new Web Form
2. optionally, do as much design as you wish using the WYSIWYG editor.
After the next two steps, you won't have this support.
3. close the file
4. rename to the .ASCX extension
5. reopen the .ASCX file and make these changes:
- Change the <%@ Page ... %> directive to <%@ Control ... %>
- remove the <html> tags, entire <head> section, <body> tags and
<form runat=server> tags (and their end tags)
6. open the code-behind class file (you'll need to Project > Show All Files
to see it) and make these changes:
- change System.Web.UI.Page to System.Web.UI.UserControl in the two
places it appears
- for C# classes only, change Page.Init to this.Init
To consume:
1. Add a Register directive to the page, pointing to the ASCX file (just
like a single file ASCX)
2. If you want to code against the user control in the codebehind class for
the ASPX page, you'll need to add an instance variable in the code behind.
For example, let's say I have a user control "mywidget.ascx" whose
code-behind class name is "mywidget", that I consume on WebForm1.aspx with
the id "m1". Further, the mywidget class defines a public member "message".
Here's how I'd set the message member programmatically:
Public Class WebForm2
Inherits System.Web.UI.Page
Protected m1 as mywidget
Sub Page_Load(sender as Object, e as EventArgs)
m1.message="Hello World"
End Sub
End Class
hth,
Susan
**********************************
"Michael Gaertner" <mgaert@b...> wrote in message
news:28945@a...
>
> Are there any examples out there of a simple code behind page that can be
> inherited from a user control/.ascx. I'm trying to provide several user
> controls with my DNS string from config.web and/or Context.Cache. Classes
> inheriting from Page are no good for .ascx pages. Classes inheriting from
> UserControl seem right, but I can't find anything about implementing the
> HttpContext object correctly for class derived from UserCotrol.
> Thanks.
>
---
http://www.asptoday.com - the leading site for timely,
in-depth information for ASP developers everywhere.
---
You are currently subscribed to aspx as: $subst('Recip.EmailAddr')
To unsubscribe send a blank email to leave-aspx-$subst('Recip.MemberIDChar')@p2p.wrox.com
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