下面是Windows.pas中的片段,请问类似{$EXTERNALSYM WCHAR}这些的语句是干什么的,什么意思? WCHAR = WideChar;
{$EXTERNALSYM WCHAR}
PWChar = PWideChar; LPSTR = PAnsiChar;
{$EXTERNALSYM LPSTR}
PLPSTR = ^LPSTR;
{$EXTERNALSYM PLPSTR}
LPCSTR = PAnsiChar;
{$EXTERNALSYM LPCSTR}
LPCTSTR = PAnsiChar; { should be PWideChar if UNICODE }
{$EXTERNALSYM LPCTSTR}
LPTSTR = PAnsiChar; { should be PWideChar if UNICODE }
{$EXTERNALSYM WCHAR}
PWChar = PWideChar; LPSTR = PAnsiChar;
{$EXTERNALSYM LPSTR}
PLPSTR = ^LPSTR;
{$EXTERNALSYM PLPSTR}
LPCSTR = PAnsiChar;
{$EXTERNALSYM LPCSTR}
LPCTSTR = PAnsiChar; { should be PWideChar if UNICODE }
{$EXTERNALSYM LPCTSTR}
LPTSTR = PAnsiChar; { should be PWideChar if UNICODE }
{$EXTERNALSYM WCHAR}还是不太明白?!WCHAR好象就不是什么specified Pascal symbol 有必要{$EXTERNALSYM WCHAR}这句话吧?!说实在,英语水平有限,还是看不太明白?!