I'm using web project and web forms.
I create Custom Class
Namespace CustomWebControls
Public Class NoValidationDDL
Inherits DropDownList
End Class
End Namespace
and i try to register this class in assembly web.config page section
<controls>
<add tagPrefix="customDDL" namespace="CustomWebControls" assembly="ae" />
</controls>
and try to use in ascx
<customDDL:NoValidationDDL ID ="id" runat="server"></customDDL:NoValidationDDL>
How can i do this in web project?
This should work (assuming the assembly name for your project is ae) - make sure that you build the project after creating/modifying your custom control. Unless updated 'ae.dll' is present in your bin directory, intellisense etc will not work.
Instead of modify web.config, you may also try register control at page(aspx) or control(ascx) level by adding register directive after page directive:
<%# Register Assembly="ae" Namespace="CustomWebControls" TagPrefix="customDDL" %>
Related
I have an asp.net page where I need to read some appSetting value from web.config. After googling, I found that I can use this code:
using System.Web.Configuration;
WebConfigurationManager.AppSettings["configFile"]
but after I insert the line using System.Web.Configuration by typing in this at my aspx page
<%# Using System.Web.Configuration; %>
I got this error: ASP.net runtime error. Only content controls are allowed directly in a content page that contains Content control. So how can I read the system web configuration file from my asp page if it doesn't allow me to import System.Web.Configuration?
I think this should do the trick (I've never used WebConfigutationManager but this works for me).
Code Behind
using System.Configuration
protected string GetForgottenUrl()
{
return ConfigurationManager.AppSettings["SomeKey"];
}
Aspx Page
<a href='<%= GetForgottenUrl()%>'>Forgot Password</a>
Web.Config
<configuration>
<appSettings>
<add key="SomeKey" value="SomePage.aspx" />
</appSettings>
</configuration>
EDIT:: You may need to add a reference to System.Configuration
Please see the code below (Image Hander):
<%# WebHandler Language="VB" Class="com.Genie.PresentationLayer.Web.ImageHandler1" %>
Imports com.Genie.BusinessLogicLayer
Namespace com.Genie.PresentationLayer.Web
Public Class ImageHandler1
Inherits ImageHandler
Private p1 as Person
Public Sub New()
End Sub
end class
end namespace
com.Genie.BusinessLogicLayer was added to the GAC today. The application produces a runtime error when it gets to the Image Handler: 'Type Person is not defined'. Adding an assembly to the web.config as follows resolves the problem:
<assemblies>
<add assembly="BusinessLogicLayer, Version=1.0.0.0, Culture=neutral, PublicKeyToken="669e0ddf0bb1aa2a"/>
</assemblies>
Why do I have to amend the web.config? I thought 'Add Assembly' was for website projects that do not use MSBuild (and therefore do not have 'References'). This is a web application project.
The references you add to a project are used when the project is compiled, but an ASPX page or ASHX handler is compiled when it is first requested. At this time the references are lost, so you'll need to provide them yourself.
The alternative would be precompiling your ASPX pages, causing the error to be caught at compiletime as opposed to runtime, or moving the code to codebehind so your project's references will be used.
I created a simple custom control that only inherits from the Literal control, and doesn't have any extensions yet, code is empty.
Namespace: CustomControls
Class name: Literal : System.Web.UI.WebControls.Literal
Next thing I do is registering this control in the aspx page as following:
<%# Register TagPrefix="web" Namespace="CustomControls" %>
(I read in few tutorials that this is one of the ways to register it, besides web.config etc.)
After all, no intellisence for me, and worse- I get a parse error 'unknown server tag: web' when I try to run the page with the control in it.
I used 'create new project' and not new website, in case this info is needed.
What could be my problem?
Thanks in advance.
Here is how I did it, step by step starting from nothing. This first method uses a second project/assembly. For the App_code version scroll down.
Web Application Project Method
Create a new ASP.Net Web Application. Take note of the name, mine is called WebApplication2. If you already have an existing web application, which is likely, double click the properties section of your project and check the "Assembly Name" property, make note of it.
Create a new Class in the web applcation named Literal.cs
Put in code similar to the following for the class defenition:
namespace CustomControls
{
public class Literal : System.Web.UI.WebControls.Literal
{
}
}
Add the following register tag to the top of your aspx page
<%# Register assembly="WebApplication2" namespace="CustomControls" tagprefix="web" %>
If your assembly name was different then change it here. I noticed that when I did this in VB.Net the namespace was WebApplication1.CustomControls instead of just CustomControls like it was in C#, kind of odd.
Add the new control to your page:
<web:Literal ID="Literal1" runat="server" Text="test" />
Seperate Project Method
Create a new Empty Website (ASP.Net).
Add a new ASP.Net Server Control library named CustomControls to the solution.
Add a new Class to the new project called Literal (I'm using C# so my file is named Literal.cs). Below is my super basic code, that I believe should match the code described in the question.
namespace CustomControls
{
public class Literal : System.Web.UI.WebControls.Literal
{
}
}
Add a reference to the CustomControls project to your website.
Add the assembly registration to the top of your aspx page:
<%# Register assembly="CustomControls" namespace="CustomControls" tagprefix="web" %>
Add a new instance of the control to your page:
<web:Literal ID="Literal1" runat="server" Text="test" />
In App_Code Method
Create a new Empty Website (ASP.Net).
Add a new Class to the App_Code folder Literal2 (I'm using C# so my file is named Literal2.cs). Below is my super basic code, that I believe should match the code described in the question. I called it 2 so that you can use this in conjunction with the method described above without getting compile errors
namespace CustomControls
{
public class Literal2 : System.Web.UI.WebControls.Literal
{
}
}
Register the assembly/namespace for app_code in your aspx page by adding the following line to the top
<%# Register Namespace="CustomControls" Assembly="__code" tagprefix="web" %>
Add an instance of the new control to your page:
<web:Literal2 ID="literal2" runat="server" Text="test2" />
I tested this using visual studio and it all worked fine for me.
You can also register your control in web.config if you would like to use it on other pages
<pages>
<controls>
<add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add tagPrefix="asp" namespace="System.Web.UI.WebControls" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add tagPrefix="web" namespace="MyProject.CustomControls" assembly="MyProject" />
</controls>
</pages>
For web site this will work
<add tagPrefix ="web" namespace="ASP.App_Code.CustomControls" />
The problem lies in your <%# Register TagPrefix="web" Namespace="CustomControls" %> tag: it misses the assembly name!
It must become <%# Register TagPrefix="web" Namespace="CustomControls" Assembly="YourAssemblyName" %>. If you have difficulties finding the assembly name for your class here are a few hints:
If you created the class inside the web application's Visual Studio project, or in a separate DLL (shared library) project, then right-click the project and go to Properties to get the assembly name
If you created the .cs file in App_Code directory, ASP.App_Code should work
Otherwise please give us some information about project layout!
The easiest thing to do is to drag-and-drop the Literal.ascx on to the page (if the page is in the same solution) .If the page is another solution, you could add the control to VS toolbox and drag-and-drop the control on the page.
You forgot the src attribute.
<%# Register TagPrefix="web" Namespace="CustomControls" Src="PathToYourCustomControl" %>
I have a classlibrary. This library contains widget.ascx control. How to load this webusercontrol from web. I know "LoadControl". But this not applicable.
How can i load web usercontrol from library?
2009.09.24
My main goal is i'm creating addon based web application. Every addon will be widget of web application.
I need dynamically load web usercontrol from library
You need to add a reference of the library to your web project.
Then instantiate it as you would with any other control, either programatically or in an #Register directive.
Kindness,
Dan
In addition to obviously adding the DLL to your project references, you also need to register the control. You can do this on each page that will use the control, but I usually prefer to do it in web.config. As a quick example, here's the line I used to register the Infragistics UltraWebGrid control in my app.
<pages>
<controls>
<add tagPrefix="ig" namespace="Infragistics.WebUI.UltraWebGrid" assembly="Infragistics35.WebUI.UltraWebGrid.v8.2, Version=8.2.20082.1000, Culture=neutral, PublicKeyToken=7DD5C3163F2CD0CB"/>
</controls>
</pages>
TagPrefix works kind of like an in-page namespace, so if I had a bunch of controls I was importing from one DLL, they'd probably all have the same TagPrefix. In the page, I'd simply reference my control as follows:
<ig:UltraWebGrid runat="server" SetSomeOtherPropertiesToo="blah" />
I am not sure how the .ascx file is added to your class library. Normally user controls are loaded using LoadControl which requires an existing file. In case the user control is compiled as embedded resource in your class library you could use GetManifestResourceStream() to read the user controls' contents and then ParseControl to create a control from the string read using GetManifestResourceStream.
I'm trying to use System.Web.UI.TemplateControl.LoadControl to build a templated web part for a SharePoint application, and I'm having trouble with a control that references an external assembly.
I have a user control with the first few lines like this:
<%# Control Language="C#" ClassName="MyControl" %>
<%# Assembly Name="AjaxControlToolkit" %>
<%# Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
The web part derives from a base webpart that implements the templating and some other utilities which is in an assembly called "MyWebParts" (for example), while the derived web part class is in "MyProject". MyProject has a reference to "MyWebParts" (obviously), and to "AjaxControlToolkit", but "MyWebParts" does not have a reference to "AjaxControlToolkit". At runtime, when the templated web part tries to load the user control (a .ascx file in the "controltemplates" SharePoint root folder), it calls the base methods it inherited across assemblies, and it throws an HttpParseException, indicating that it couldn't load a required assembly. The EventViewer confirms that the assembly in question is AjaxControlToolkit.
I tried adding the AjaxControlToolkit assembly to the web.config for sharepoint, and it's sitting in the GAC, but to no avail.
Anyone know how I can do this without having a reference to every assembly in existence in my "MyWebParts" assembly?
Add a reference to your assembly in the web.config assemblies section, this will force sharepoint to load that assembly into memory, like so:
<assemblies>
<add assembly="AjaxControlToolkit, Version=1.0.10920.16768, Culture=neutral, PublicKeyToken=28f01b0e84b6d53e"/>
</assemblies>
P.S. this is for ajax 1.0, correct the assembly version if you are using the AJAX 3.5 version.