Is there any way to inject dependencies into an Immediacy CMS control using Spring.NET, ideally without having to use to ContextRegistry when initialising
the control?
Update, with my own answer
The issue here is that Immediacy already has a handler defined in web.config that deals with all aspx pages, & so it's not possible add an entry for Spring.NET's PageHandlerFactory in web.config as per a normal webforms app. That rules out making
the control implement ISupportsWebDependencyInjection. Furthermore, most of Immediacy's generated pages are aspx pages that don't physically exist on
the drive. I have changed
the title of
the question to reflect this.
What I have done to get Dependency Injection working is:
Add
the usual entries to web.config for Spring.NET as outlined in
the documentation, except for
the adding
the entry to
the <httpHandlers> section. In this case I've got my object definitions in Spring.config.
Create
the following abstract base class that will deal with all of
the Dependency Injection work:
DIControl.cs
public abstract class DIControl : ImmediacyControl
{
protected virtual string DIName
{
get
{
return this.GetType().Name;
}
}
protected override void OnInit(EventArgs e)
{
if (ContextRegistry.GetContext().GetObject(DIName, this.GetType()) != null)
ContextRegistry.GetContext().ConfigureObject(this, DIName);
base.OnInit(e);
}
}
For non-immediacy
controls, you can make this server side control inherit from Control or whatever subclass of that you like.
For any control with which you wish to use with Spring.NET's Inversion of Control container, define it to inherit from DIControl & add
the relelvant entry to Spring.config, for example:
SampleControl.cs
public class SampleControl : DIControl, INamingContainer
{
public string Text
{
get;
set;
}
protected string InjectedText
{
get;
set;
}
public SampleControl()
: base()
{
Text = "Hello world";
}
protected override void RenderContents(HtmlTextWriter output)
{
output.Write(string.Format("{0} {1}", Text, InjectedText));
}
}
Spring.config
<objects xmlns="http://www.springframework.net">
<object id="SampleControl" type="MyProject.SampleControl, MyAssembly">
<property name="InjectedText" value="from Spring.NET" />
</object>
</objects>
You can optionally override DIName if you wish to name your entry in Spring.config differently from
the name of your class.
Provided everything's done correctly, you will have
the control writing out "Hello world from Spring.NET!" when used in a page.
This solution uses Spring.NET's ContextRegistry from
within the control, but I would be surprised if there's no way around that for Immediacy at least since
the page objects themselves aren't accessible. However, can this be improved at all from a Spring.NET perspective? Is there maybe an Immediacy plugin that already does this that I'm completely unaware of? Or is there an approach that does this in a more elegant way? I'm open to suggestions.
