DIPROPHEADER is a generic structure placed at the beginning of all property structures.
typedef struct DIPROPHEADER { 
    DWORD    dwSize; 
    DWORD    dwHeaderSize; 
    DWORD    dwObj; 
    DWORD    dwHow; 
} DIPROPHEADER, *LPDIPROPHEADER; 
 
typedef const DIPROPHEADER *LPCDIPROPHEADER;
 | Value | Meaning | 
|---|---|
| DIPH_DEVICE | The dwObj member must be zero. | 
| DIPH_BYOFFSET | The dwObj member is the offset into the current data format of the object whose property is being accessed. | 
| DIPH_BYID | The dwObj member is the object type/instance identifier. This identifier is returned in the dwType member of the DIDEVICEOBJECTINSTANCE structure returned from a previous call to the IDirectInputDevice::EnumObjects member. | 
  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dinput.h.