This function returns the size in bytes of the total files in a given directory path. The function parameters are ...

ADirName : string
This is the name path to the desired directory. It can include or exclude the trailing backslash as it is resolved internally.

ARecurseDirs : boolean = true
This denotes whether to recurse Sub-Directories or not. By default Sub-Directories will recursively be processed.

Examples

    iSize := DirSize('c:\temp');   // Will recurse sub-dirs
    iSize := DirSize('c:\temp\',true)  // Same as above

    iSize := DirSize('\program files\',false);  // No sub-dir recurse

// ===========================================
// Return Total size of files in directory
// in bytes
// ===========================================

function DirSize(const ADirName : string;
                 ARecurseDirs : boolean = true) : integer;
const FIND_OK = 0;
var iResult : integer;

  // ====================
  // Recursive Routine
  // ====================
  procedure _RecurseDir(const ADirName : string);
  var sDirName : string;
      rDirInfo : TSearchRec;
      iFindResult : integer;
  begin
    sDirName := IncludeTrailingPathDelimiter(ADirName);
    iFindResult := FindFirst(sDirName + '*.*',faAnyFile,rDirInfo);

    while iFindResult = FIND_OK do begin
      // Ignore . and .. directories
      if (rDirInfo.Name[1] <> '.') then begin
        if (rDirInfo.Attr and faDirectory = faDirectory) and
          ARecurseDirs then
            _RecurseDir(sDirName + rDirInfo.Name) // Keep Recursing
        else
          inc(iResult,rDirInfo.Size);             // Accumulate Sizes
      end;

      iFindResult := FindNext(rDirInfo);
      if iFindResult <> FIND_OK then FindClose(rDirInfo);
    end;
  end;

// DirSize Main
begin
  Screen.Cursor := crHourGlass;
  Application.ProcessMessages;
  iResult := 0;
  _RecurseDir(ADirName);
  Screen.Cursor := crDefault;

  Result := iResult;
end;