Remoting over the Web in VB.NET
In this article I will explain you about Remoting over the Web in VB.NET.
It is also possible for Internet Information Server (IIS) to host remote objects.The console client project is named WebClientExe.
To use IIS as a server, you must take a number of steps:
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The remote object must be server activated.
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Map a virtual directory, on the Web server, to the SimpleObjectLib folder.
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The remote object can't be programmatically configured. It must use a web.config file in the virtual directory's root, see Listing 25.26.
Listing 25.26: Web.config
<?xml version="1.0" ?>
<configuration>
<system.runtime.remoting>
<application>
<service>
<wellknown
mode="SingleCall"
type="SimpleObjectLib.SimpleObject, SimpleObjectLib"
objectUri="Simple.rem">
</wellknown>
</service>
<channels>
<channel
name="Server-Activated Web Client"
type="System.Runtime.Remoting.Channels.Http.HttpChannel, System.Runtime.Remoting"/>
</channels>
</application>
</system.runtime.remoting>
</configuration>
You should be aware of a number of items in the configuration file:
-
No port number need be specified, as IIS has already been configured to listen on a port, normally port 80.
-
The objectUri attribute in the wellknown element must use the extension .rem or .soap.
The client code remains the same as previous server-activated examples (see Listing 25.27). The client output is shown in Figure 25.16.
Listing 25.27: WebClient.vb
Protected Sub Calendar_Selection(ByVal sender As [Object], ByVal e As EventArgs)
ChannelServices.RegisterChannel(New HttpChannel())
Dim simple As SimpleObject = Nothing
simple = DirectCast(Activator.GetObject(GetType(SimpleObject),
"http://localhost/WebRemoting/Simple.rem"), SimpleObject)
Dim ret As String = Nothing
ret = simple.ConCatString("using the", "Web for remoting.")
End Sub
Figure 25.16: WebClientExe Output
Conclusion
Hope this article would have helped you in understanding Remoting over the Web in VB.NET.