Using OPENFILENAME

**IdioticCreation** · 01-15-2007

Hey, I am really lacking in windows programming, but I'm trying to use the windows openfilename structure. It is just for a console program, I'm not registering any windows. I just want to have a simple way to load a txt file.

The part where I get thrown is what to do after the file is selected. (I think).
Here is what I have so far:

Code:

        char CurrentFileName[1024];
        OPENFILENAME OpenFilename;
        memset(&OpenFilename, 0, sizeof(OpenFilename));
        OpenFilename.lStructSize = sizeof(OpenFilename);
        OpenFilename.hwndOwner = 0;
        OpenFilename.hInstance = 0;
        OpenFilename.lpstrFilter = "Text Files (*.txt)\0*.txt\0All Files (*.*)\0*.*\0";
        OpenFilename.lpstrFile = CurrentFileName;
        OpenFilename.nMaxFile = sizeof(CurrentFileName);
        OpenFilename.Flags = OFN_FILEMUSTEXIST;
        OpenFilename.lpstrDefExt = "txt";
        
        if(GetOpenFileName(&OpenFilename)) {  //Am I using the right function here?
                //What needs to happen here?
        }

Thanks,
David

**Tonto** · 01-16-2007

I hope I'm not being rude, or stating the obvious, but you know --

http://msdn2.microsoft.com/en-us/library/ms646927.aspx
http://msdn2.microsoft.com/en-us/library/ms646839.aspx
http://msdn2.microsoft.com/en-us/library/ms646829.aspx
http://msdn2.microsoft.com/en-us/library/ms646960.aspx

**vart** · 01-16-2007

I took the sample from one of the links above... And you know - it is working.

Code:

#include <windows.h>

int main()
{
	OPENFILENAME ofn;       // common dialog box structure
	char szFile[260];       // buffer for file name
	HWND hwnd = NULL;              // owner window
	HANDLE hf;              // file handle

	// Initialize OPENFILENAME
	ZeroMemory(&ofn, sizeof(ofn));
	ofn.lStructSize = sizeof(ofn);
	ofn.hwndOwner = hwnd;
	ofn.lpstrFile = szFile;
	//
	// Set lpstrFile[0] to '\0' so that GetOpenFileName does not 
	// use the contents of szFile to initialize itself.
	//
	ofn.lpstrFile[0] = '\0';
	ofn.nMaxFile = sizeof(szFile);
	ofn.lpstrFilter = "All\0*.*\0Text\0*.TXT\0";
	ofn.nFilterIndex = 1;
	ofn.lpstrFileTitle = NULL;
	ofn.nMaxFileTitle = 0;
	ofn.lpstrInitialDir = NULL;
	ofn.Flags = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;

	// Display the Open dialog box. 

	if (GetOpenFileName(&ofn)==TRUE) 
		hf = CreateFile(ofn.lpstrFile, GENERIC_READ,
			0, (LPSECURITY_ATTRIBUTES) NULL,
			OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,
			(HANDLE) NULL);

	return 0;
}

**IdioticCreation** · 01-16-2007

Ok, sorry about the ignorant question, but it appears that all those links explain how to open the save and open dialog boxes. Once you select a file, is it possible to use if and of streams on the chosen file. I guess the filename that you get from GetOpenFileName is a lp, and I don't think you can use that with if/of stream

Thanks for being patient with me,
David

**Tonto** · 01-16-2007

>> I guess the filename that you get from GetOpenFileName is a lp, and I don't think you can use that with if/of stream

Nope. In fact, it is usable, and it is in the array 'char szFile[260];'. Simple put, ofn.lpstrFile points to, or is essentially an alias for, szFile, and is written to by GetOpenFileName

**IdioticCreation** · 01-16-2007

Awesome! That worked. I had been trying to use the lpstrFile from the structure.....I wonder about my self sometimes.

Thanks, Tonto!

**Tonto** · 01-16-2007

Well, just beating a dead horse, with a flail, you should be able to use the lpstrFile from the structure to do it. I'd delight in seeing the compiler errors <salivating>

**IdioticCreation** · 01-16-2007

Huh, your right. That also worked, but before I wasn't setting lpstrFile to null. Or maybe I'm getting confused build error when I forgot to include the comdlg32.lib. I don't really know, because I'm sleepy and stupid....stupid-sleepy.

Sorry if I got your hopes up

**CornedBee** · 01-16-2007

One more thing, though. Doing it this way is not unicode-compatible.
Coming up with a good solution has some issues:
-- The standard streams, whether in their wide or narrow variant, take a narrow-character string as the file name. This means that in Unicode builds, you have to convert from UTF-16 to some narrow encoding. (This is an often-complained-about problem with the streams.)
-- The filenames could contain characters that are not representable in any narrow encoding but UTF-8, which would render such files unopenable by your code as unknown characters get replaced by question marks.
-- Windows does not support UTF-8 as a narrow encoding.

All in all, the situation is a mess. There is no good solution, really, except finding some 3rd-party components that provide a stream interface for wide-character file names.

**IdioticCreation** · 01-16-2007

Hey, thanks for the information CornedBee. That kinda sucks, but it's not that big a deal because it was just a learning program. An encryptor actaully.

Thread: Using OPENFILENAME

Thread Tools

Search Thread

Display

Using OPENFILENAME

Similar Threads

Save vs Save As.... OPENFILENAME flags

Openfilename

OPENFILENAME structure

OPENFILENAME ofn;

OPENFILENAME and multiple files.