mischelpfunctions.pas

Gantt source file example to use in delphi 7

   Result := DaysBetween(StartDate, Enddate);
end;



function GetDaysInTheMonth(StartDate: TDateTime; Month: Integer): Integer;
var
   Year: Word;
begin
   Year := YearOf(StartDate);
   Result := DaysInAMonth(Year, Month);
end;



function SpanOfNowAndThen(const ANow, AThen: TDateTime): TDateTime;
begin
   Result := Abs(ANow - AThen);
end;

//Function Added by Jacek
Function GetDaysApart(const Date1, Date2 : TDateTime):Longint;
begin
    Result := Trunc(Date2) - Trunc(Date1);
end;




function CanDraw(StartDate, EndDate, GridStart: TDatetime; TimeType: TGanttTimeType): Boolean;
var
   ItemStart, ItemEnd, GridDate,TempDate : TDateTime;
begin
   Result := False;
   GridDate := DateOf(GridStart);   // Grid Start Date
   ItemStart := DateOf(StartDate);  // Item End Date
   ItemEnd := DateOf(EndDate);      //Item Start Date;
If TimeType = ttday then
begin
     if (ItemStart <= GridDate) and (ItemEnd >= GridDate) then Result := True;
     exit;
end
else
If TimeType = tthour then
begin
     if (ItemStart <= GridDate) and (ItemEnd >= GridDate) then Result := True;
     exit;
end
else
begin
   Result := True;
end;
end;






function GetTimeFromStart(StartDate, EndDate, GridStart: TDatetime; TimeType: TGanttTimeType): Integer;
var
   ItemStart, ItemEnd, GridDate : TDateTime;
begin
   GridDate := DateOf(GridStart);   // Grid Start Date
   ItemStart := DateOf(StartDate);  // Item End Date
   ItemEnd := DateOf(EndDate);      //Item Start Date;

if not CanDraw(StartDate, EndDate, GridStart, TimeType) then
begin
  Result := 0;
  exit;
end;

If TimeType = ttday then
begin
   if (ItemStart = GridDate) then Result := Hourof(StartDate)
   else
     if (ItemStart < GridDate) and (ItemEnd > GridDate) then Result := 0
     else
       Result := -1;
   exit;
end
else
If TimeType = tthour then
begin
   if (ItemStart = GridDate) then Result := MinuteOf(StartDate)
   else
     if (ItemStart < GridDate) and (ItemEnd > GridDate) then Result := 0
     else
       Result := -1;
   exit;
end
else
begin
   if (ItemStart < GridDate) then
      Result := -1
   else
      Result := GetDaysApart(GridDate, ItemStart);
end;
end;



function GetTimeLeft(StartDate, EndDate, GridStart: TDateTime; TimeType: TGanttTimeType): Integer;
var
   Start: TDateTime;
   TimeBetween : Int64;
   Hour,Min,Sec,MSec : Word;
begin
   if StartDate > GridStart then Start := StartDate
    else
      Start := GridStart; // start of chart

if not CanDraw(StartDate, EndDate, GridStart, TimeType) then
begin
  Result := 0;
  exit;
end;

If TimeType = ttday then
begin
   TimeBetween := HoursBetween(Start, Enddate);
   DecodeTime(Enddate, Hour, Min, Sec, MSec);

   if TimeBetween >= 24 then TimeBetween := 24  // just for drawing purposes
    else TimeBetween := Hour;

   if (Enddate < Start) then TimeBetween := -1;
   Result := TimeBetween;
   exit;
end
else
If TimeType = tthour then
begin
    TimeBetween := MinutesBetween(Start, Enddate);
    DecodeTime(Enddate, Hour, Min, Sec, MSec);

    if TimeBetween >= 60 then TimeBetween := 60  // just for drawing purposes
      else TimeBetween := Min;

   if (Enddate < Start) then TimeBetween := -1;
   Result := TimeBetween;
   exit;
end
else
begin
   if (Enddate < Start) then
      Result := -1
   else
      Result := GetDaysApart(Start, Enddate); //DaysBetween(Start, Enddate);
end;
end;




function GetDaysFromStart(StartDate, GridStart: Tdatetime; StartMonth: Integer): Integer;
var
   Start, Enddate: TDateTime;
begin
//
//   Start := EncodeDate(YearOf(GridStart), MonthOf(GridStart), 1); // start of chart
   Start := GridStart; // start of chart
   Enddate := StartDate;//DateOf(StartDate);
   if Start>Enddate then
    Result := DaysBetween(Start, Enddate)*-1
   else
    Result := DaysBetween(Start, Enddate);
end;


function GetDaysLeft(StartDate, GridStart: TDateTime; StartMonth, Days: Integer): Integer; overload;
var
   Start, Enddate: TDateTime;
begin
//   Start := EncodeDate(YearOf(Now), StartMonth, 1); // start of chart
   Start := GridStart; // start of chart
   Enddate := incDay(StartDate, Days); // end of project item
   if (Enddate < Start) then
      Result := -1
   else
      Result := DaysBetween(Start, Enddate);
end;


function GetDaysLeft(StartDate, GridDate: TDateTime; Days: Integer): Integer; overload;
var
   Start, Enddate: TDateTime;
begin
//   Start := EncodeDate(YearOf(GridDate), MonthOf(GridDate), 1); // start of chart
   Start := GridDate; // start of chart
   Enddate := incDay(StartDate, Days); // end of project item
   if (Enddate < Start) then
      Result := -1
   else
      Result := DaysBetween(Start, Enddate);
end;

function GetFirstDayofMonth (const ADate: TDateTime): TDateTime;
var Day,Month,Year : Word;
begin
	DecodeDate(ADate,Year,Month,Day);
	Result := EncodeDate(Year,Month,1);
end;


Function GetDateAsTitle(MyDate : TDateTime; FLanguage : TGanttLanguageValue) : String;
Var
  StartDate : TDateTime;
  DayNo : Double;
  Hour,Min,Sec,MSec : Word;
begin
 StartDate := 0.0;
 DayNo := DaySpan(MyDate,StartDate);
 DecodeTime(MyDate, Hour, Min, Sec, MSec);
 Result := IntToStr(Trunc(DayNo)) + ' '+FLanguage.DaysString+', ' + Inttostr(Hour) + ' '+FLanguage.HourString+', ' +IntToStr(Min) +' '+ FLanguage.MinuteString;
end;





function ISOWeeksInYear (const Year: Word): Byte;
var
	DOW: Integer;
begin
	DOW := ISODayOfWeek (GetFirstDayOfYear (Year));
	if (DOW = 4) or ((DOW = 3) and IsLeapYear (Year)) then
		Result := 53
	else
		Result :=52;
end;


function ISODayOfWeek (const DT: TDateTime): Integer;
begin
	Result := DayOfWeek (DT);
	Dec (Result);
	if Result = 0 then
		Result := 7;
end;



function StartOfISOWeek (const DT: TDateTime): TDateTime;
begin
	Result := DT - ISODayOfWeek (DT) + 1;
end;

function EndOfISOWeek (const DT: TDateTime): TDateTime;
begin
	Result := DT - ISODayOfWeek (DT) + 7;
end;

function GetFirstDayOfYear (const Year: Word): TDateTime;
begin
	Result := EncodeDate (Year, 1, 1);
end;


procedure Date2ISOWeekNo (const DT: TDateTime; var WeekNo: Byte;
	var Year: Word);
var
	FirstMonday, StartYear: TDateTime;
	WeekOfs: Byte;
begin
	Year := YearOf (DT);
	StartYear := GetFirstDayOfYear (Year) + 3; // Jan 4th
	if ISODayOfWeek (StartYear) <= 4 then
	begin
		FirstMonday := StartOfISOWeek (StartYear);
		WeekOfs := 1;
		if DT < FirstMonday then
		begin
			Dec (Year);
			WeekNo := ISOWeeksInYear (Year);
			Exit;
		end;
	end
	else
	begin
		FirstMonday := StartOfISOWeek (StartYear) + 7;
		WeekOfs := 2;
		if DT < FirstMonday then
		begin
			WeekNo := 1;
			Exit;
		end;
	end;
	WeekNo := GetDaysApart (FirstMonday, StartofISOWeek (DT)) div 7 + WeekOfs;
	if WeekNo > ISOWeeksInYear (Year) then
	begin
		WeekNo := 1;
		Inc (Year);
	end;
end;


function LInt2EStr (const L: LongInt): String;
begin
	try
		Result := IntToStr (L);
	except
		Result := '';
	end;
end;


function FillStr (const Ch : Char; const N : Integer): string;
begin
	SetLength (Result, N);
	FillChar (Result [1], N, Ch);
end;

function LeftStr (const S : string; const N : Integer): string;
begin
	Result := Copy (S, 1, N);
end;

function PadChLeftStr (const S : string; const Ch : Char;
	const Len : Integer): string;
var
	N: Integer;
begin
	N := Length (S);
	if N < Len then
		Result := FillStr (Ch, Len - N) + S
	else
		Result := S;
end;


function LInt2ZStr (const L: LongInt; const Len: Byte): String;
begin
	Result := LInt2EStr (L);
	Result := PadChLeftStr (LeftStr (Result, Len), '0', Len);
end;



function Date2ISOWeekStr (const DT: TDateTime; weekstring: string): string;
var
	WeekNo: Byte;
	Year: Word;
begin
	Date2ISOWeekNo (DT, WeekNo, Year);
  //modif jpm
	Result := weekstring + ' ' + LInt2ZStr (WeekNo, 2);
end;



{function MinimizeString(Canvas : TCanvas; aString: string; aMaxLength: integer): string;
const
   cDots = '...';
var
   i : integer;
begin
   Result := '';
   if aString = '' then Exit;
   try
   if Canvas.TextWidth(aString) < aMaxLength then
   begin
      Result := aString;
      exit;
   end;
   // find a space to add dots
   for i := Length(aString) downto 1 do
      if aString[i] = ' ' then
         if Canvas.TextWidth(Copy(aString, 1, i - 1) + cDots) <= aMaxLength then
         begin
            Result := Copy(aString, 1, i - 1) + cDots;
            break;
         end;

   // force the dots within string
   if Result = '' then
     for i := Length(aString) downto 1 do
         if Canvas.TextWidth(Copy(aString, 1, i - 1) + cDots) <= aMaxLength then
            Result := Copy(aString, 1, i - 1) + cDots;
   finally
       Canvas.free;
   end;
   // only show first
   if Result = '' then
      Result := aString[1] + cDots;
end;      }



end.