sample of sorting algoritm for collection of Invoice objects by date-time

Collection is type of System.Collections.Generic.List

// sorting class 
public class InvoiceSorterbyDueDate : System.Collections.Generic.IComparer<BaseObject>
    {
        #region IComparer<Invoice> Members
        public int Compare(BaseObject x, BaseObject y){
            return ((Invoice)x).DueDate.CompareTo(((Invoice)y).DueDate);
        }
        #endregion
    }


  //call
  IComparer<BaseObject> ins  = new InvoiceSorterbyDueDate();
  p.InvoiceCollectionToCheck.Sort(ins);

  //    

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