Click here to Skip to main content
15,353,841 members
Articles / Programming Languages / C#
Posted 30 Apr 2012

Tagged as


4 bookmarked

Integrating REST Into an Existing C# Application

Rate me:
Please Sign up or sign in to vote.
4.00/5 (1 vote)
30 Apr 2012CPOL2 min read
Most articles I read about REST and C# apps concerned themselves with starting fresh whereas I needed to add REST to an existing application. This articles describes the process.


I was trying to add REST web services to an existing C# application. I could only find information as to how to create a new C# REST app, but very little on retrofitting older apps. The results below are not complicated but are the culmination of an afternoon's research.

The Solution

First, create a new public interface for the service contract:

using System;
using System.Collections.Generic;
using System.Text;
using System.ServiceModel;
using System.ServiceModel.Web;

namespace bob
    public interface IService
        [WebGet(UriTemplate = "/GetSoftwareVersion", ResponseFormat=WebMessageFormat.Json)]
        String GetSoftwareVersion();

Here, I've defined a new interface called IService. Note the two ServiceModel namespaces I'm using.... very important. Also, you will need to include the references by the same name into your project.

I then defined a new method I want to call via REST called GetSoftwareVersion. The UriTemplate states what you add (/GetSoftwareVersion) to the base URI (spec'ed elsewhere, but currently set to 'http://localhost:10870') to form the URI needed to call this method. The ResponseFormat stipulates that I want the data returned using JSON format, rather than the standard XML.

Next, I define a class to implement this interface and therefore my REST services.

using System;
using System.Collections.Generic;
using System.Text;
using System.ServiceModel;
using System.ServiceModel.Web;

namespace bob
    public class RestService : IService
        /// <summary>
        /// Gets the version
        /// </summary>
        /// <returns>The Version String</returns>
        public String GetSoftwareVersion()
            return App.Instance.GetSoftwareVersion();

My new class, RestService, implements the interface, or service contract, I defined earlier. Again, note the ServiceModel references. Since we also have a gSOAP (C++) interface, rather than completely re-jigging the main App class (which has a singleton for external access) or making the RestService a singleton itself (which might be useful down the road for other reasons), I just point the REST service to the existing method. Simple and it works.

Next, the app.config needs to be tweaked:

        <service name="bob.RestService">
            <endpoint binding="webHttpBinding" contract="bob.IService"
            <behavior name="webHttp">

Things of note are the service name (bob.RestService) and endpoint contract (bob.IService). Point the service name at the REST implementation class and the contract at the interface.

I then "borrowed" the ThreadedServiceHost class from here, changed the ServiceHost class reference to WebServiceHost, updated the project reference, removed the endpoint and associated code (simplified things), and made a call to start it from the App() (constructor) ala:

// Fire up REST web services.
restHost = new ThreadedWebServiceHost<RestService>(Properties.Settings.Default.REST_ENDPOINT);

REST_ENDPOINT is simply the base URI where my services are located (http://localhost:10870/App). Compile and point your browser at http://localhost:10870/App/GetSoftwareVersion. You should see the result on screen.



This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Web Developer
Canada Canada
No Biography provided

Comments and Discussions

-- There are no messages in this forum --