一个简单的工作日计算：

function getWorkDay(dtBegin:TDateTime;IncDays:Integer):TDateTime;const  days: array[1..7] of string=('7','1','2','3','4', '5','6');var  week1:string;  x:integer;  holiday:TStrings;begin  //初始化节假日，  holiday:=TStringList.Create;  //TODO:从数据库中取，此为演示  holiday.Add('2014-10-01');  holiday.Add('2014-10-02');  //and so on ...  try    //日期    x:=1;    while (x<=IncDays) do    begin      //判断是否周末      week1:=days[DayOfWeek(dtBegin)];      //今日周几      if (week1='6') or (week1='7') or (holiday.IndexOf(FormatDateTime('yyyy-mm-dd',dtBegin))>=0) then      begin        dtBegin:=IncDay(dtBegin,1);        Continue;      end      else      begin        dtBegin:=IncDay(dtBegin,1);        x:=x+1;      end;    end;    Result:=dtBegin;  finally    holiday.Free;  end;end;