很急，一个伤心伤脑筋的问题！Delphi好难学啊

...
var
  p: TPoint;
begin
  GetCaretPos(p);
...

上面的GetCaretPos是啥意思，啥时候要带参数啥时候没有参数？

API函数

The GetCaretPos function copies the caret's position, in client coordinates, to the specified POINT structure. 

BOOL GetCaretPos(

  LPPOINT lpPoint // address of structure to receive coordinates
  );
 

Parameters

lpPoint

Points to the POINT structure that is to receive the client coordinates of the caret. 

 

Return Values

If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError. 

Remarks

The caret position is always given in the client coordinates of the window that contains the caret.

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