WCF Lesson 4:-Fault Contract in WCF

Fault Contract in WCF

With the help of fault contract we can describe how to exchange error information from service to client. If we get any error in the service then we can pass this error information from service to client with the help of Fault contract.

For Example:-

Everybody is familiar with the error DivideByZero. It occurs when we try to divide a number with zero, It occurs this exception. Same example I am using here.

I create Error class which will be used to pass to the client at the time of error occur:-

[DataContract]

public class Error

{

    [DataMember]

    public string ErrorMessage;

    [DataMember]

    public string ErrorMethod;

}

Now declare the method in contract class. While creating the method you have to assign the fault contract to the method and describe the type of error which we pass to the client. Here it is the type of Error Class.

[ServiceContract]

public interface ITechAltum

{

    [OperationContract]

    [FaultContract(typeof(Error))]

    int div(int x, int y);

}

Now implement this method in the Class where we use exception handling.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.ServiceModel;

public class TechAltum:ITechAltum

{

    public int div(int x, int y)

    {

        try

        {

            int z = x / y;

            return z;

        }

        catch(Exception e)

        {

            Error er=new Error();

            er.ErrorMessage="You attempted to divide by zero";

            er.ErrorMethod="Div";

            throw new FaultException<Error>(er);

       

        }

   

    }

}

Now implement it at the client side:-

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.ServiceModel;

public partial class _Default : System.Web.UI.Page

{

    protected void Page_Load(object sender, EventArgs e)

    {

        try

        {

            ServiceReference1.TechAltumClient svctech = new ServiceReference1.TechAltumClient();

            int z = svctech.div(5, 0);

        }

        catch (FaultException<ServiceReference1.Error> er)

        {

            Response.Write(er.Detail.ErrorMessage);

            Response.Write(er.Detail.ErrorMethod);

       

        }

    }

}

Hope you enjoyed the article.

Note:-kindly add namespace System.ServiceModel where you use falut contract.