Mega Code Archive

Endofaday - generate a tdatetime value set to the very end of a day dateutils unit

1 function EndOfADay ( const Year, Month, Day : Word ) : TDateTime; 2 function EndOfADay ( const Year, DayOfYear : Word ) : TDateTime; Description The EndOfADay function generates a TDateTime value set to the given year, month and day with a time set to 1 milli-second before midnight. Version 1 Allows the Month and Day to be specified separately. The month must be between 1 (January) and 12 (December). The day must be between 1 and 31, depending on the year and month. Version 2 Allows the Month and Day to be specified as a DayOfYear instead. Notes WARNING there appears to be a bug in Delphi (as tested by the author using Delphi 7.0 Professional build 4.453), where the long syntax version incorrectly uses the EndOfAMonth routine to calculate the end of the day. Errors in the parameter values gives EConvertError. Related commands EndOfAMonth Generate a TDateTime value set to the very end of a month Example code : Set the date to last msec of the 20th century - illustrates Delphi bug var mydate : TDateTime; begin myDate := EndOfADay(1999, 365); // Ensure that milli-seconds are shown LongTimeFormat := 'hh:mm:ss.zzz'; ShowMessage('End of 1999 using short syntax = '+DateTimeToStr(myDate)); myDate := EndOfADay(1999, 12, 31); // Ensure that milli-seconds are shown LongTimeFormat := 'hh:mm:ss.zzz'; ShowMessage('End of 1999 using long syntax = '+DateTimeToStr(myDate)); ShowMessage('WARNING - The above value is incorrect'); end; Show full unit code End of 1999 using short syntax = 31/12/1999 23:59:59.999 End of 1999 using long syntax = 30/01/2000 23:59:59.999 WARNING - The above value is incorrect