Why doesn't this work?

Why doesn't the BROWSE dialog appear?

Code:

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                    OPENFILENAME file_data;

                    file_data.lStructSize = 50;
                    file_data.hwndOwner = hwnd;
                    file_data.hInstance = hInst;
                    file_data.lpstrFilter = NULL;
                    file_data.lpstrCustomFilter = NULL;
                    file_data.nMaxCustFilter = 40;
                    file_data.nFilterIndex = NULL;
                    file_data.lpstrFile = NULL;
                    file_data.nMaxFile = 256;
                    file_data.lpstrFileTitle = NULL;
                    file_data.nMaxFileTitle = NULL;
                    file_data.lpstrInitialDir = NULL;
                    file_data.lpstrTitle = NULL;
                    file_data.Flags = OFN_ALLOWMULTISELECT;
                    file_data.nFileOffset = NULL;
                    file_data.nFileExtension = NULL;
                    file_data.lpstrDefExt = NULL;
                    file_data.lCustData = NULL;
                    file_data.lpfnHook = NULL;
                    file_data.lpTemplateName = NULL;

                    GetOpenFileName(&file_data);
                    MessageBox(hwnd, file_data.lpstrFile, "the file", 0);

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You should always check return codes. If GetOpenFileName returns FALSE you can obtain error information through:

Code:

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DWORD CommDlgExtendedError(VOID).

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It look suspicous that you set lStructSize to 50. Are you sure that

Code:

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sizeof(OPENFILENAME) == 50

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?

Well...there are several errors in your code...

Code:

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file_data.lStructSize = 50;

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As already mentioned...this flag should be set in the following way:

Quote:

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Windows NT 4.0: In an application that is compiled with WINVER and _WIN32_WINNT >= 0x0500, use OPENFILENAME_SIZE_VERSION_400 for this member.

Windows 2000/XP: Use sizeof (OPENFILENAME) for this parameter.

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Code:

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file_data.hInstance = hInst;

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You are setting an instance handle, however, this member is ignored as long as neither the 'OFN_ENABLETEMPLATEHANDLE' nor the 'OFN_ENBALETEMPLATE' flag is set within the 'Flags' member which is not the case in your example...

Code:

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file_data.lpstrCustomFilter = NULL;
file_data.nMaxCustFilter = 40;

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With the two lines you are specifying that 'lpstrCustomFilter' points to an allocated memory buffer of 40 bytes which is not the case...this member gets ignored.

Code:

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file_data.lpstrFile = NULL;
file_data.nMaxFile = 256;

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With the two lines you are specifying that 'lpstrFile' points to an allocated memory buffer of 256 bytes which is not the case...

Code:

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MessageBox(hwnd, file_data.lpstrFile, "the file", 0);

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With this line you are trying to display the selected filename. However, as I mentioned before you did not supply a valid buffer to the member 'lpstrFile' which you are trying to dereference now. This most-likely will crash your application immediately...

Can anyone please give me an example?

Quote:

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Originally posted by Devil Panther
Can anyone please give me an example?

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Code:

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char        szExtBuffer[MAX_PATH] = "";
OPENFILENAME ofn;

strcpy(szExtBuffer, "*.txt; *.log");

ofn.lStructSize      = sizeof(ofn);
ofn.hwndOwner        = 0;
ofn.hInstance        = 0;
ofn.lpstrFilter      = 0;
ofn.lpstrCustomFilter = 0;
ofn.nMaxCustFilter    = 0;
ofn.nFilterIndex      = 0;
ofn.lpstrFile        = szExtBuffer;
ofn.nMaxFile          = MAX_PATH;
ofn.lpstrFileTitle    = 0;
ofn.nMaxFileTitle    = 0;
ofn.lpstrInitialDir  = 0;
ofn.lpstrTitle        = "Open file";
ofn.Flags            = 0;
ofn.nFileOffset      = 0;
ofn.nFileExtension    = 0;
ofn.lpstrDefExt      = 0;
ofn.lCustData        = 0;
ofn.lpfnHook          = 0;
ofn.lpTemplateName    = 0;

// Open dialog
if(::GetOpenFileName(&ofn) == FALSE)
  [COLOR=#008800]// Cancel pressed

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****... it fails, and doesn't show any dialog box... why???

btw, I'm using borland C++ 5.5.

The following works correctly. Also, this should work on any Windows compiler.

Code:

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#include <windows.h>
#include <stdio.h>

int main()
{
  char        szExtBuffer[MAX_PATH] = "";
  OPENFILENAME ofn;
  strcpy(szExtBuffer, "*.txt; *.log");
  memset(&ofn, 0, sizeof(ofn));
  ofn.lStructSize      = sizeof(ofn);
  ofn.lpstrFile        = szExtBuffer;
  ofn.nMaxFile          = MAX_PATH;
  ofn.lpstrTitle        = "Open file";

  // Open dialog
  if(::GetOpenFileName(&ofn) == FALSE)
  {
  }
  return 0;
}

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Compiles cleanly, and displays the File open dialog.

Regards,

Paul McKenzie

It does not show me anything...