ObjectPascal
Yesterday
Function
Gives the date yesterday DateUtils unit
 function Yesterday : TDateTime;
Description
The Yesterday function returns yesterdays date in the local time zone.
 
Because the return value is a TDateTime type, the time component is set to zero.
 
The TDateTime type can be processed by many SysUtil and Dateutils routines.(start of day).
Related commands
Date Gives the current date
Now Gives the current date and time
Time Gives the current time
Tomorrow Gives the date tomorrow
 
Example code : Show yesterday, today and tomorrows dates
begin
  WriteLn('Yesterday = '+DateToStr(Yesterday));
  WriteLn('Today     = '+DateToStr(Date));
  WriteLn('Tomorrow  = '+DateToStr(tomorrow));

  WriteLn('Yesterday''s time = '+TimeToStr(Yesterday));
end;
Show full unit code
   Yesterday = 28/10/2002
   Today     = 29/10/2002
   Tomorrow  = 30/10/2002
   Yesterday's time = 00:00:00