Suggest how to extract method

Question

I have 3 methods(* BindingSource are bindingsources, context is data context, cache* -are some List for cache operations):

 private void AddUpdateRowDocuments()
 {
 try
 {
 tRANSMITDOCDOCUMENTSRELATIONSBindingSource.EndEdit();
 var t = tRANSMITDOCDOCUMENTSRELATIONSBindingSource.Current as WcfDataServiceReference.TRANSMIT_DOC_DOCUMENTS_RELATIONS;
 if (t.TRANSMIT_DOC_ID == 0)
 {
 if (!cachetddrList.Contains(t))
 {
 cachetddrList.Add(t);
 }
 return;
 }
 context.UpdateObject(t);
 }
 catch (Exception ex)
 {
 logger.ErrorException(string.Empty, ex);
 }
 }
private void AddUpdateRowOrganizations()
 {
 try
 {
 tRANSMITDOCORGANIZATIONRELATIONSBindingSource.EndEdit();
 var t = tRANSMITDOCORGANIZATIONRELATIONSBindingSource.Current as WcfDataServiceReference.TRANSMIT_DOC_ORGANIZATION_RELATIONS;
 if (t.TRANSMIT_DOC_ID == 0)
 {
 if (!cachetdorList.Contains(t))
 {
 cachetdorList.Add(t);
 }
 return;
 }
 context.UpdateObject(t);
 }
 catch (Exception ex)
 {
 logger.ErrorException(string.Empty, ex);
 }
 }
private void AddUpdateRowPartators()
 {
 try
 {
 tRANSMITDOCPARTATORRELATIONSBindingSource.EndEdit();
 var t = tRANSMITDOCPARTATORRELATIONSBindingSource.Current as WcfDataServiceReference.TRANSMIT_DOC_PARTATOR_RELATIONS;
 if (t.TRANSMIT_DOC_ID == 0)
 {
 if (!cachetdprList.Contains(t))
 {
 cachetdprList.Add(t);
 }
 return;
 }
 context.UpdateObject(t);
 }
 catch (Exception ex)
 {
 logger.ErrorException(string.Empty, ex);
 }
 }

Any thoughts on how to improve them? My inner sense says that they can be turned into one generic method, but i have little experience with generics, so cant say if i am right.

Answer 1

Something along the lines of this. Generics aren't that difficult. Just replace every occurance of 'some desired type' with the generic identifier.

private void AddUpdateRow<T>(BindingSource bindingSource, List<T> cachedList)
 where T : ITransmitDocId
{
 try
 {
 bindingSource.EndEdit();
 T t = bindingSource.Current as T;
 if (t.TRANSMIT_DOC_ID == 0)
 {
 if (!cachedList.Contains(t))
 {
 cachedList.Add(t);
 }
 return;
 }
 context.UpdateObject(t);
 }
 catch (Exception ex)
 {
 logger.ErrorException(string.Empty, ex);
 }
}

The where constraint in the function definition should indicate a common interface/class in which TRANSMIT_DOC_ID is defined.

• 0x49D1: problem with t.TRANSMIT_DOC_ID: 'T' does not contain a definition for 'TRANSMIT_DOC_ID' and no extension method 'TRANSMIT_DOC_ID' accepting a first argument of type 'T' could be found (are you missing a using directive or an assembly reference?)
• Steven Jeuris: @nihi_l_ist: How are you calling this method? Does the error occur in the generic function or on the caller? Be sure to replace T with your desired type when calling the function. E.g. AddUpdateRow<CourtWcfDataServiceReference.TRANSMIT_DOC_ORGANIZATION_RELATIONS>( bindingSource, cachedList ).
• 0x49D1: It appears in generic method(code does't even compile)..Think T must implement some interface that should be common for all that classes(like TRANSMIT_DOC_ORGANIZATION_RELATIONS and ets..)
• 0x49D1: Ok...thank you anyway .. I'll move that t.TRANSMIT_DOC_ID to method's parameters and that all..Code will become a bit wired, but it WILL wwork :) thanks for the answer.
• Steven Jeuris: @nihi_l_ist: oh I see the problem now! you can add a where clause to the function ... to indicate T is at least an interface you define which defines TRANSMIT_DOC_ID. WIll update the answer.