System.Data.DataRow.GetRecordFromVersion C# (CSharp) Method

        internal int GetRecordFromVersion(DataRowVersion version)
        {
            switch (version)
            {
                case DataRowVersion.Original:
                    return GetOriginalRecordNo();
                case DataRowVersion.Current:
                    return GetCurrentRecordNo();
                case DataRowVersion.Proposed:
                    return GetProposedRecordNo();
                case DataRowVersion.Default:
                    return GetDefaultRecord();
                default:
                    throw ExceptionBuilder.InvalidRowVersion();
            }
        }

        internal override object Eval(DataRow row, DataRowVersion version)
        {
            if (!found)
            {
#if DEBUG
                if (CompModSwitches.NameNode.TraceVerbose)
                {
                    Debug.WriteLine("Can not find column " + name);
                }
#endif
                throw ExprException.UnboundName(name);
            }

            if (row == null)
            {
                if (IsTableConstant()) // this column is TableConstant Aggregate Function
                {
                    return(column.DataExpression.Evaluate());
                }
                else
                {
#if DEBUG
                    if (CompModSwitches.NameNode.TraceVerbose)
                    {
                        Debug.WriteLine("Can not eval column without a row.." + name);
                    }
#endif
                    throw ExprException.UnboundName(name);
                }
            }

            return(column[row.GetRecordFromVersion(version)]);
        }