获得自增列

                    cmd.CommandText="SELECT     COLUMNPROPERTY(     OBJECT_ID('"+_TableName+"'), '"+col.Name+"', 'IsIdentity' )   ";
                    reader= cmd.ExecuteReader();
                    i = 0;
                    if (reader.Read()) i = reader.GetInt32(0);
                    reader.Close();
                    if (i==1)
                    {
                        col.isAutoIncrease = true;
                        cmd.CommandText = "select   IDENT_SEED( '" + _TableName + "')  as  seedvalue,IDENT_INCR   (   '" + _TableName + "'   )   as increvalue  ";
                        reader = cmd.ExecuteReader();
                        if (reader.Read())
                        {
                                col.AutoIncrementSeed =Convert.ToInt32( reader.GetValue(0));
                                col.AutoIncrementStep =Convert.ToInt32( reader.GetValue(1));
                        }
                        reader.Close();
                    }