An Introduction To .NET Remoting - Creating The Shared Library

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Fire up Visual Studio.NET. Click on File->New->Project. Choose to create a new "C# Library" and name it ResumeServerLibrary then click on OK. This will create the "shared vocabulary" that both our .NET Remote client and Server will use to communicate.

The full code is shown below. If you would like to skip the database access portions, replace the ResumeLoader object with:

public class ResumeLoader : System.MarshalByRefObject
{

public ResumeLoader()
{
System.Console.WriteLine("New Referance Added!");
}

public Resume GetResumeByUserID(decimal userID)
{
return new Resume(1);
}
}

If you're getting errors that the System.Runtime.Remoting.Channels.Tcp namespace does not exist, make sure that you’ve added a reference to the System.Runtime.Remoting.dll by clicking on the Project->Add Reference menu.

using System;
using System.Runtime;
using System.Data.SqlClient;

The namespace we're using for this particular object is DotNetRemoteTest. The object shown below is a MarshalByRefObject, which means that instead of passing ResumeLoader over the wire, we're creating a reference and all of the work including the database work happens completely on the server side.

namespace DotNetRemoteTest
{

public class ResumeLoader : System.MarshalByRefObject
{
private SqlConnection dbConnection;

public ResumeLoader()
{
this.dbConnection = new System.Data.SqlClient.SqlConnection();
this.dbConnection.ConnectionString =
"data source=GRIMSAADO2K;initial catalog=underground;integrated security=SSPI;pers" +
"ist security info=True;workstation id=GRIMSAADO2K;packet size=4096";
System.Console.WriteLine("New Referance Added!");
}

public Resume GetResumeByUserID(decimal userID)
{
Resume resume = new Resume();
try
{
dbConnection.Open();
SqlCommand cmd = new SqlCommand(
"SELECT ResumeID, UserID, Title, Body FROM Resume as theResume WHERE theResume.UserID="+ userID +""
, dbConnection
);
SqlDataReader aReader = cmd.ExecuteReader();
if(aReader.Read())
{
resume.ResumeID=aReader.GetDecimal(0);
resume.UserID=aReader.GetDecimal(1);
resume.Title=aReader.GetString(2);
resume.Body=aReader.GetString(3);
}
aReader.Close();
dbConnection.Close();
}
catch(Exception x) { resume.Title="Error:"+x; }
return resume;
}
}

The Resume object needs to be serializable in order to be a return type of a remotely referenced .NET Remote object. The reason for this is the object will have to be turned into raw data to be passed over the network and then re-assembled into an object again at the other end.

This object is extremely simple, and to add to the simplicity of this tutorial, the constructor even initializes the fields with some default content:

[Serializable]
public class Resume
{
private decimal resumeID, userID;
private String body, title;

public Resume(decimal resumeID)
{
this.ResumeID=resumeID;
this.UserID=1;
this.Body="This is the default body of the resume";
this.Title="This is the default Title";
}

public decimal ResumeID
{
get { return resumeID; }
set { this.resumeID=value; }
}
public decimal UserID
{
get { return userID; }
set { this.userID=value; }
}
public String Body
{
get { return body; }
set
{
this.body=value;
}
}
public String Title
{
get { return title; }
set
{ this.title=value; }
}

}//END OF RESUME OBJECT

}//END OF DotNetRemoteTest namespace

Next: The Server Object >>
 

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