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See also:
- How to position the GETPRINTER() dialog
- Using Extended MessageBox() Class
- Extended MessageBox Class
- How to change font name and size in the MessageBox dialog
- Creating an Open dialog box to specify the drive, directory, and name of a file to open (Shell32 version)
- Creating the Open dialog box to specify the drive, directory, and name of a file to open
- How to display a dialog box that enables the user to select a folder (an alternative to the GETDIR)
DO decl
* some of the bit flags for the dialog
#DEFINE OFN_HIDEREADONLY 4
#DEFINE OFN_NOCHANGEDIR 8
#DEFINE OFN_EXTENSIONDIFFERENT 0x400
#DEFINE OFN_PATHMUSTEXIST 0x800
#DEFINE OFN_CREATEPROMPT 0x2000
#DEFINE OFN_EXPLORER 0x80000
#DEFINE OFN_DONTADDTORECENT 0x2000000
*| typedef struct tagOFN {
*| DWORD lStructSize; 0:4
*| HWND hwndOwner; 4:4
*| HINSTANCE hInstance; 8:4
*| LPCTSTR lpstrFilter; 12:4
*| LPTSTR lpstrCustFilt; 16:4
*| DWORD nMaxCustFilter; 20:4
*| DWORD nFilterIndex; 24:4
*| LPTSTR lpstrFile; 28:4
*| DWORD nMaxFile; 32:4
*| LPTSTR lpstrFileTitle; 36:4
*| DWORD nMaxFileTitle; 40:4
*| LPCTSTR lpstrInitialDir; 44:4
*| LPCTSTR lpstrTitle; 48:4
*| DWORD Flags; 52:4
*| WORD nFileOffset; 56:2
*| WORD nFileExtension; 58:2
*| LPCTSTR lpstrDefExt; 60:4
*| LPARAM lCustData; 64:4
*| LPOFNHOOKPROC lpfnHook; 68:4
*| LPCTSTR lpTemplateName; 72:4 = 76 bytes
*| #if (_WIN32_WINNT >= 0x0500)
*| void * pvReserved; 76:4
*| DWORD dwReserved; 80:4
*| DWORD FlagsEx; 84:4
*| #endif // (_WIN32_WINNT >= 0x0500)
*| } OPENFILENAME, *LPOPENFILENAME; total = 88 bytes
#DEFINE OPENFILENAME_SIZE 76 && set to 88 for W2K
LOCAL lcBuffer, loFilter, loFilename, loFilenameRet,;
loTitlebar, loDefExt, lnFlags, lnFileOffset, lnExtOffset,;
lcFullname, lcPath, lcFilename, lcFileext
loFilter = CreateObject("PChar",;
"Text Files" + Chr(0) + "*.txt;*.bak" + Chr(0)+Chr(0))
loFilename = CreateObject("PChar", Padr("myfile.txt", 250,Chr(0)))
loFilenameRet = CreateObject("PChar", Repli(Chr(0),250))
loTitlebar = CreateObject("PChar",;
"Will you save this file at least?")
loDefExt = CreateObject("PChar", "TXT")
lnFlags = OFN_PATHMUSTEXIST + OFN_EXTENSIONDIFFERENT +;
OFN_CREATEPROMPT + OFN_HIDEREADONLY + OFN_NOCHANGEDIR
* compiling the OPENFILENAME structure
* Rem: initdir - default chosen
lcBuffer = num2dword(OPENFILENAME_SIZE) +;
num2dword(GetActiveWindow()) +;
num2dword(0) +;
num2dword(loFilter.GetAddr()) +;
num2dword(0) +;
num2dword(0) +;
num2dword(1) +;
num2dword(loFilename.GetAddr()) +;
num2dword(loFilename.GetAllocSize()) +;
num2dword(loFilenameRet.GetAddr()) +;
num2dword(loFilenameRet.GetAllocSize()) +;
num2dword(0) +;
num2dword(loTitlebar.GetAddr()) +;
num2dword(lnFlags) +;
num2dword(0) +;
num2dword(loDefExt.GetAddr()) +;
num2dword(0) +;
num2dword(0) +;
num2dword(0)
* creating a Save dialog box using the prepared structure
IF GetSaveFileName (@lcBuffer) = 0
LOCAL lnErrorCode
lnErrorCode = CommDlgExtendedError()
IF lnErrorCode <> 0
? "Error code:", lnErrorCode
ELSE
* the Cancel button selected
ENDIF
ELSE
lcFullname = STRTRAN(Trim(loFilename.GetValue()), Chr(0),"")
lcFilename = STRTRAN(Trim(loFilenameRet.GetValue()), Chr(0),"")
lnFileOffset = buf2word(SUBSTR(lcBuffer, 57,2))
lnExtOffset = buf2word(SUBSTR(lcBuffer, 59,2))
lcPath = SUBSTR(lcFullname, 1, lnFileOffset-1)
lcFileext = SUBSTR(lcFullname, lnExtOffset+1)
? lcFullname
? lcPath
? lcFilename
? lcFileext
ENDIF
* end of main
FUNCTION num2dword (lnValue)
#DEFINE m0 256
#DEFINE m1 65536
#DEFINE m2 16777216
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 buf2word (lcBuffer)
RETURN Asc(SUBSTR(lcBuffer, 1,1)) + ;
Asc(SUBSTR(lcBuffer, 2,1)) * 256
DEFINE CLASS PChar As Custom
PROTECTED hMem
PROCEDURE Init (lcString)
THIS.hMem = 0
THIS.setValue (lcString)
PROCEDURE Destroy
THIS.ReleaseString
FUNCTION getAddr && returns a pointer to the string
RETURN THIS.hMem
FUNCTION getValue && returns string value
LOCAL lnSize, lcBuffer
lnSize = THIS.getAllocSize()
lcBuffer = SPACE(lnSize)
IF THIS.hMem <> 0
DECLARE RtlMoveMemory IN kernel32 As Heap2Str;
STRING @, INTEGER, INTEGER
= Heap2Str (@lcBuffer, THIS.hMem, lnSize)
ENDIF
RETURN lcBuffer
FUNCTION getAllocSize && returns allocated memory size (string length)
DECLARE INTEGER GlobalSize IN kernel32 INTEGER hMem
RETURN Iif(THIS.hMem=0, 0, GlobalSize(THIS.hMem))
PROCEDURE setValue (lcString) && assigns new string value
#DEFINE GMEM_FIXED 0
THIS.ReleaseString
DECLARE INTEGER GlobalAlloc IN kernel32 INTEGER, INTEGER
DECLARE RtlMoveMemory IN kernel32 As Str2Heap;
INTEGER, STRING @, INTEGER
LOCAL lnSize
lcString = lcString + Chr(0)
lnSize = Len(lcString)
THIS.hMem = GlobalAlloc (GMEM_FIXED, lnSize)
IF THIS.hMem <> 0
= Str2Heap (THIS.hMem, @lcString, lnSize)
ENDIF
PROCEDURE ReleaseString && releases allocated memory
IF THIS.hMem <> 0
DECLARE INTEGER GlobalFree IN kernel32 INTEGER
= GlobalFree (THIS.hMem)
THIS.hMem = 0
ENDIF
ENDDEFINE
PROCEDURE decl
DECLARE INTEGER GetActiveWindow IN user32
DECLARE INTEGER GlobalFree IN kernel32 INTEGER hMem
DECLARE INTEGER GetSaveFileName IN comdlg32 STRING @lpofn
DECLARE INTEGER CommDlgExtendedError IN comdlg32 CommDlgExtendedError
GetActiveWindow
GetSaveFileName
GlobalAlloc
GlobalFree
GlobalSize
The OPENFILENAME structure length depends on the OS, and can be 76 or 88 bytes.
This is important, because invalid parameter creates an error. Note that this structure is used with GetOpenFileName and GetSaveFileName functions. There is substantial set of OFN flags to control the dialog behaviour.
To fill the OPENFILENAME structure -- as well as almost all other Comdlg structures used -- you need not just strings but pointers to strings. There is a class PChar in this examples, which creates such extended strings. In more simple cases the StrDup is quite enough to accomplish this task.