Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

unit ExtractEmailsFunc;

 interface

 uses
   Windows, SysUtils;

 procedure CheckEMail(FilePath: string);

 implementation

 var
   BufferSize: Integer;

 function VerifyFile(strFileName: string): Integer;
 var
   intErro: Integer;
   tsrFile: TSearchRec;
 begin
   intErro := FindFirst(strFileName, FaAnyFile, tsrFile);
   if intErro = 0 then Result := tsrFile.Size
    else
      Result := -1;
   FindClose(tsrFile);
 end;

 procedure CheckEMail(FilePath: string);
 var
   I: Integer;
   hFile: Integer;
   Buffer: PChar;
   StrEmail: string;
 begin
   hFile := FileOpen(FilePath, fmOpenRead);
   try
     if hFile = 0 then Exit;
     GetMem(Buffer, bufferSize + 1);
     ZeroMemory(Buffer, BufferSize + 1);
     try
       FileRead(hFile, Buffer^, BufferSize);
       I := 0;
       while I <= BufferSize - 1 do
        begin
         StrEmail := '';
         if Buffer[I] = '<' then
          begin
           Inc(I);
           while (Buffer[I] <> '@') and (I <= BufferSize) do
            begin
             if (Buffer[I] = CHR(45)) or (Buffer[I] = CHR(46)) or
               (Buffer[I] = CHR(90)) or ((Buffer[I] > CHR(49)) and (Buffer[I] <= CHR(57)))
               or ((Buffer[I] >= CHR(65)) and (Buffer[I] <= CHR(90))) or
               ((Buffer[I] >= CHR(97)) and (Buffer[I] <= CHR(122))) then
              begin
               StrEmail := StrEmail + Buffer[I];
             end
              else
              begin
               StrEmail := '';
               Break;
             end;
             Inc(I);
           end;
           if StrEmail <> '' then
            begin
             StrEmail := StrEmail + '@';
             Inc(I);
             while (Buffer[I] <> '.') and (I <= BufferSize) do
              begin
               if (Buffer[I] = CHR(45)) or (Buffer[I] = CHR(46)) or
                 (Buffer[I] = CHR(90)) or ((Buffer[I] >= CHR(49)) and (Buffer[I] <= CHR(57)))
                 or ((Buffer[I] >= CHR(65)) and (Buffer[I] <= CHR(90))) or
                 ((Buffer[I] >= CHR(97)) and (Buffer[I] <= CHR(122))) then
                begin
                 StrEmail := StrEmail + Buffer[I];
               end
                else
                begin
                 StrEmail := '';
                 Break;
               end;
               Inc(I);
             end;
             if StrEmail <> '' then
              begin
               StrEmail := StrEmail + '.';
               Inc(i);
               while (Buffer[I] <> '>') and (I <= BufferSize) do
                begin
                 if (Buffer[I] = CHR(45)) or (Buffer[I] = CHR(46)) or
                   (Buffer[I] = CHR(90)) or ((Buffer[I] >= CHR(49)) and (Buffer[I] <= CHR(57)))
                   or ((Buffer[I] >= CHR(65)) and (Buffer[I] <= CHR(90))) or
                   ((Buffer[I] >= CHR(97)) and (Buffer[I] <= CHR(122))) then
                  begin
                   StrEmail := StrEmail + Buffer[I];
                 end
                  else
                  begin
                   StrEmail := '';
                   Break;
                 end;
                 Inc(I);
               end;
               if StrEmail <> '' then
                begin
                 WriteLn(StrEmail);
                 Inc(I);
               end;
             end;
           end;
         end
          else
            Inc(I);
       end;
     finally
       FreeMem(Buffer);
     end;
   finally
     FileClose(hFile);
   end;
 end;

 begin
   BufferSize := VerifyFile(ParamStr(1));
   if BufferSize <= 0 then Exit;
   CheckEMail(ParamStr(1));
 end.