Author: Ernesto De Spirito

How can I get the dates of the first and last day of the month of a given date?

Answer:

FDOM and LDOM 

FDOM returns the date that corresponds to the first day of the same month as the 
date passed as parameter, while LDOM returns the date that corresponds to the last 
day of the month (subtracting 1 from the date that corresponds to the first day of 
the next month). 

1   function FDOM(Date: TDateTime): TDateTime;
2   var
3     Year, Month, Day: Word;
4   begin
5     DecodeDate(Date, Year, Month, Day);
6     Result := EncodeDate(Year, Month, 1);
7   end;
8   
9   function LDOM(Date: TDateTime): TDateTime;
10  var
11    Year, Month, Day: Word;
12  begin
13    DecodeDate(Date, Year, Month, Day);
14    if Month < 12 then
15      inc(Month)
16    else
17    begin
18      Month := 1;
19      inc(Year)
20    end;
21    Result := EncodeDate(Year, Month, 1) - 1;
22  end;
23  
24  //Sample call 
25  
26  procedure TForm1.Button1Click(Sender: TObject);
27  begin
28    ShowMessage(DateToStr(FDOM(Now)));
29    ShowMessage(DateToStr(LDOM(Now)));
30  end;


Copyright (c) 2001 Ernesto De Spiritomailto:edspirito@latiumsoftware.com
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