在Delphi 中有一个date日期操作的函数库，直接引用系统单元DateUtils就可以了，里边有很多日期时间的操作函数，包含年份加减，月份加减，天数加减，小时加减，分钟加减，秒钟加减等，下面是这些函数的原型，直接调用函数就可以了。

function IncYear(const AValue: TDateTime;
  const ANumberOfYears: Integer): TDateTime;
begin
  Result := IncMonth(AValue, ANumberOfYears * MonthsPerYear);
end;

function IncWeek(const AValue: TDateTime;
  const ANumberOfWeeks: Integer): TDateTime;
begin
  Result := AValue + ANumberOfWeeks * DaysPerWeek;
end;

function IncDay(const AValue: TDateTime;
  const ANumberOfDays: Integer): TDateTime;
begin
  Result := AValue + ANumberOfDays;
end;

function IncHour(const AValue: TDateTime;
  const ANumberOfHours: Int64): TDateTime;
begin
  Result := ((AValue * HoursPerDay) + ANumberOfHours) / HoursPerDay;
end;

function IncMinute(const AValue: TDateTime;
  const ANumberOfMinutes: Int64): TDateTime;
begin
  Result := ((AValue * MinsPerDay) + ANumberOfMinutes) / MinsPerDay;
end;

function IncSecond(const AValue: TDateTime;
  const ANumberOfSeconds: Int64): TDateTime;
begin
  Result := ((AValue * SecsPerDay) + ANumberOfSeconds) / SecsPerDay;
end;

function IncMilliSecond(const AValue: TDateTime;
  const ANumberOfMilliSeconds: Int64): TDateTime;
begin
  Result := ((AValue * MSecsPerDay) + ANumberOfMilliSeconds) / MSecsPerDay;
end;