WIN32API使用“选择颜色”函数

DO declare

#DEFINE CC_RGBINIT 1
#DEFINE CC_FULLOPEN 2
#DEFINE CC_PREVENTFULLOPEN 4
#DEFINE CC_SHOWHELP 8
#DEFINE CC_SOLIDCOLOR 128
#DEFINE CC_ANYCOLOR 256
#DEFINE CC_WIDE 32

*| typedef struct {
*|   DWORD        lStructSize;      0:4
*|   HWND         hwndOwner;        4:4
*|   HWND         hInstance;        8:4
*|   COLORREF     rgbResult;       12:4
*|   COLORREF   * lpCustColors;    16:4
*|   DWORD        Flags;           20:4
*|   LPARAM       lCustData;       24:4
*|   LPCCHOOKPROC lpfnHook;        28:4
*|   LPCTSTR      lpTemplateName;  32:4
*| } CHOOSECOLOR, *LPCHOOSECOLOR; total=36 bytes

#DEFINE CHOOSECOLOR_SIZE     36

*| typedef DWORD COLORREF;
*| typedef DWORD *LPCOLORREF;
*| 0x00bbggrr
#DEFINE COLORREF_ARRAY_SIZE  64

LOCAL hWindow, lcBuffer, lnInitColor, lnFlags,;
  lnCustColors, lcCustColors, ii

hWindow = GetActiveWindow()

* the color initially selected when the dialog box is created
lnInitColor = Rgb(128,0,0)

* allocating memory block for 16 COLORREF values (DWORD)
* for the custom color boxes in the dialog box
* and filling this memory with zeroes

#DEFINE GMEM_FIXED 0
lnCustColors = GlobalAlloc(GMEM_FIXED, COLORREF_ARRAY_SIZE)
= ZeroMemory(lnCustColors, COLORREF_ARRAY_SIZE)

* initialization flags
lnFlags = CC_FULLOPEN + CC_RGBINIT

* compiling the CHOOSECOLOR structure
lcBuffer = num2dword(CHOOSECOLOR_SIZE) +;
  num2dword(hWindow) +;
  num2dword(0) +;
  num2dword(lnInitColor) +;
  num2dword(lnCustColors) +;
  num2dword(lnFlags) +;
  num2dword(0) +;
  num2dword(0) +;
  num2dword(0)

IF ChooseColor(@lcBuffer) <> 0
* the OK button of the dialog box has been selected
  ? "Color selected:", buf2dword(SUBSTR(lcBuffer, 13,4))

  ? "Custom colors stored:"
  
  * copying the memory block content to a VFP string
  * just to have an opportunity to work with its substring;
  * quite weird way, though not much choice available
  * considering the VFP specifics

  lcCustColors = Repli(Chr(0), COLORREF_ARRAY_SIZE)
  = Heap2Str(@lcCustColors, lnCustColors, COLORREF_ARRAY_SIZE)

  FOR ii=1 TO 16
    ? ii, buf2dword(SUBSTR(lcCustColors, (ii-1)*4+1, 4))
  ENDFOR
ENDIF

* free the memory block if you do not use it for the
* following calls to this function
= GlobalFree(lnCustColors)

* end of main

FUNCTION num2dword (lnValue)
#DEFINE m0 0x100
#DEFINE m1 0x10000
#DEFINE m2 0x1000000
  LOCAL b0, b1, b2, b3
  b3 = Int(lnValue/m2)
  b2 = Int((lnValue - b3*m2)/m1)
  b1 = Int((lnValue - b3*m2 - b2*m1)/m0)
  b0 = Mod(lnValue, m0)
RETURN Chr(b0)+Chr(b1)+Chr(b2)+Chr(b3)

FUNCTION buf2dword (lcBuffer)
#DEFINE MAX_DWORD 0xffffffff
#DEFINE MAX_LONG 0x7FFFFFFF
  LOCAL lnResult
  lnResult = Asc(SUBSTR(lcBuffer, 1,1)) + ;
    Asc(SUBSTR(lcBuffer, 2,1)) * 256 +;
    Asc(SUBSTR(lcBuffer, 3,1)) * 65536 +;
    Asc(SUBSTR(lcBuffer, 4,1)) * 16777216
RETURN IIF(lnResult>MAX_LONG, lnResult-MAX_DWORD, lnResult)

PROCEDURE declare
  DECLARE INTEGER ChooseColor IN comdlg32 STRING @lpcc
  DECLARE INTEGER GetActiveWindow IN user32
  DECLARE INTEGER GlobalFree IN kernel32 INTEGER hMem
  DECLARE RtlZeroMemory IN kernel32 As ZeroMemory;
    INTEGER dest, INTEGER numBytes

  DECLARE INTEGER GlobalAlloc IN kernel32;
    INTEGER wFlags, INTEGER dwBytes

  DECLARE RtlMoveMemory IN kernel32 As Heap2Str;
      STRING @, INTEGER, INTEGER