[System.ServiceModel.ServiceContractAttribute(
    Namespace = "http://Microsoft.ServiceModel.Samples")]
public interface IAdd
{

    [System.ServiceModel.OperationContractAttribute(
        Action = "http://Microsoft.ServiceModel.Samples/IAdd/Add", 
        ReplyAction = "http://Microsoft.ServiceModel.Samples/IAdd/AddResponse")]
    double Add(double n1, double n2);

}

public interface IAddChannel : IAdd, System.ServiceModel.IClientChannel
{
}

public partial class AddClient : System.ServiceModel.ClientBase<IAdd>, IAdd
{

    public AddClient()
    {
    }

    public AddClient(string endpointConfigurationName)
        :
            base(endpointConfigurationName)
    {
    }

    public AddClient(System.ServiceModel.Channels.Binding binding, System.ServiceModel.EndpointAddress address)
        :
            base(binding, address)
    {
    }

    public double Add(double n1, double n2)
    {
        return base.Channel.Add(n1, n2);
    }

}