C#

public interface iCR
        {
            int CB_IO_Init(int slaveIndex);
            int WritePortReady();
            int WritePortBusy();
            void initCRData(byte[] writeBuffer, byte[] statusBuffer, int SlaveIndex, USB_Comm.CB cb, int cr_Type);
            int ProcessTWriting(ref Byte[] writeDat, ref Byte[] statusDat, ref Byte[] dataDumpWriteCheck);
            void Failure(String message);
            void Success(String message);

        }

namespace CR_Factory
    {

    public class Cr
    {
         
    }  

    public class CRFactory
    {
        public enum CRType
        {
            CR0,
            CR1,
            CR3,
            CR4,
            CR5,
            CR6
        }

        public CRFactory()
        {
        }

        public iCR GetCR(CRType type) 
        {
            iCR cr = null;
            switch (type)
            {
                case CRType.CR5:
                    cr = new CR5(); 
                    break;
                case CRType.CR6:
                    //not done yet
                    break;
                default:
                    throw new ArgumentException(string.Format("A CR of type {0} cannot be found", Enum.GetName(typeof(CRType), type)));
            }
            return cr;
        }

        public CRType DetermineCR_Type(int type)
        {
            switch (type)
            {
                case 0:
                    return CRType.CR0;
                //break;
                case 1:
                    return CRType.CR1;
                case 3:
                    return CRType.CR3;
                case 4:
                    return CRType.CR4;
                case 5:
                    return CRType.CR5;
                case 6:
                    return CRType.CR6;
                default:
                    throw new ArgumentException(string.Format("A type of type {0} cannot be found", type));

            }
        }

        }
    }

public class CR5 : iCR **compile error CR5_new.CR5 does not implement interface member iCR.initCRData(byte[],byte[],int,USB_Comm.CB,int)
    {        
        CB_703 cb_specific = null;
		
        //constructor
        public CR5()
        {
            cb_specific = new CB_703(SlaveIndex);
        }

        public void initCRData(byte[] writeBuffer, byte[] statusBuffer, int slaveIndex, USB_Comm.CB cb_specificInstance, int crType)
        {...
        }

        public int CB_IO_Init(int SlaveIndex)
        {
            int result = -534;
            result = cb_specific.IO_Init(SlaveIndex);
            return result;
        }
    .
    .
    .
    }

namespace CrWr
    {
    
    public partial class PControl : UserControl
    {
        //setup 
	
        //constructor
        public PControl()
        {
            
        }

        /// <summary>
        /// Get the P Control for chosen dll
        /// </summary>
        public Control GetPControl(USB_Comm.CB cbInstance, string dllSelected, THandlerApplication.Temp.TEMP[] temp, string dll, SC.SC.S_C c0)
        {
            cb = cbInstance;
            createControls();
            itsDll = dll;
            tArr = temp;
            cert = c0;
      
            CR_Factory.CRFactory factory = new CR_Factory.CRFactory();
            CRFactory.CRType type = factory.DetermineCR_Type(cr_Type);
            try
            {
                cr = factory.GetCR(type);             }
            catch (Exception ex)
            {
                Console.WriteLine(ex.InnerException);
            }
            return this;
        }

    private void OnP()
        {
            int result = -536;
            
            while (rL)
            {
                result = cr.CB_IO_Init(SlaveIndex); 
                if (result == 0)
                {
                    …
                }
            }

    .
    .
    .
    }