2015-02-05-parallel-looping-and-returning-1-collection-in-c.cs

List opportunities = new List(); 
var sync = new object(); 

Parallel.ForEach(proxyOpportunities, (proxyOpportunity) => 
{ 
  try 
  { 
    Opportunity convertedOpportunity = proxyOpportunity.ConvertToOpportunity(); 
    lock (sync) 
    { 
      opportunities.Add(convertedOpportunity); 
    } 
  }
  catch (Exception ex) 
  { 
    Opportunity failedOpportunity = new Opportunity() 
    { 
      ExcludeForImport = ExcludeReason.ImportFailed, 
      DocumentNumber = proxyOpportunity.With(x => x.DOC_ID) 
    }; 
    
    lock (sync) 
    { 
    opportunities.Add(failedOpportunity); 
    }
    
    LoggingWrapper logger = new LoggingWrapper();
    logger.LogError(ex); 
    } 
});

return opportunities;