set @nbillcode=(select top 1 BillCode from BillTest order by BillCode Desc)
set @lastcode=cast(substring(@nbillcode,11,1) as char)
set @ac=ascii(@lastcode)
if(@ac<=57 and @ac>=47)--如果最后一位为数字
begin
set @endcode=right('000'+cast(substring(@nbillcode,9,3)+1 as varchar(3)),3)
end
else--如果最后一位为字母
begin
set @endcode=right('000'+char(@ac+1),3)
end