BOOL ReadFile(

    HANDLE hFile,	// handle of file to read 
    LPVOID lpBuffer,	// address of buffer that receives data  
    DWORD nNumberOfBytesToRead,	// number of bytes to read 
    LPDWORD lpNumberOfBytesRead,	// address of number of bytes read 
    LPOVERLAPPED lpOverlapped 	// address of structure for data 
   );

    isbn := '';
    i:=  1 ;
    CharArray[ 0 ] := '#';
    while CharArray[i- 1 ]<> chr( 13 ) do
      begin
       ReadFile(hCom, CharArray[i],  1 , dwRead, nil);
       inc(i);
      end;
    for j:=  1  to i- 2  do isbn := isbn + CharArray[j];  
    edISBN.Text := isbn;