Programming Forums > Application Development > C++

Chesso · Mar 10th, 2006, 8:11 AM

I have written a DLL for a Delphi application I am making and decided to have the Open/Save dialog
functionality within an external DLL instead of inside the application.

The problem is I have to hard code the buffer which makes the DLL much larger then it should be.

I have read on MSDN about this problem but it really does not help as I am not too proficient with C++ in
general as I only use it when I need it. I have found plenty of article about this issue but they only explain
how to solve it using MFC with VS. I am however using Dev-CPP enviroment.

Here is the function source:

(Toggle Plain Text)

std::string OpenSaveDialog(int Open, char* InitDir)
{
 OPENFILENAME ofn;
 char szFileName[21000] = "";
 string FData("");
    
 ZeroMemory(&ofn, sizeof(OPENFILENAME));
 ofn.lStructSize = sizeof(OPENFILENAME);
 ofn.hwndOwner = NULL;
 ofn.lpstrFile = szFileName;
 ofn.nMaxFile = 21000;
 
 switch(Open)
 {
  case 0: break;
  case 1:
    ofn.lpstrFilter = "All Supported Files\0*.mp3;*.mp2;*.wav;*.wma;*.mid;*.ogg\0";
    ofn.lpstrInitialDir = InitDir;
    ofn.Flags = OFN_EXPLORER | OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_ALLOWMULTISELECT;
    
    if (GetOpenFileName(&ofn))
    {
     int len = strlen(ofn.lpstrFile);
     
     if( ofn.lpstrFile[len + 1] == 0) { return ofn.lpstrFile; } // If single file was selected.
     else {
     // This is the directory.
      FData = ofn.lpstrFile;
     
      ofn.lpstrFile += len + 1;
      while(ofn.lpstrFile[0]) {
     
     // This will contain the current file name from multiple selection.
      FData = FData + "|" + ofn.lpstrFile;      
      
      // Find next name
      len = strlen(ofn.lpstrFile);
      ofn.lpstrFile += len + 1;
      } 
       return FData;                        
     }
    }
    else { return "CANCEL"; }
  break;
  case 2: 
    ofn.lpstrFilter = "All Supported Files\0*.sm3l;*.sm3;*.m3u;*.pls\0";
    ofn.lpstrInitialDir = InitDir;
    ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY;
    ofn.lpstrDefExt = "sm3l";
    
    if (GetOpenFileName(&ofn)) { return ofn.lpstrFile; }
    else { return "CANCEL"; }
  break;  
  case 3:
    ofn.lpstrFilter = "SM3 format\0*.sm3\0M3U Format\0*.m3u\0PLS Format\0*.pls\0";
    ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
    ofn.lpstrDefExt = "sm3l";
    
    if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; }
    else { return "CANCEL"; }                                   
 }
}

Does anyone know how to solve this issue? From what I read on MSDN I need some sort of callback function to resize the buffer if necessary and read something about calling it twice.....

nnxion · Mar 10th, 2006, 9:00 AM

Quote:

Originally Posted by MSDN

nMaxFile
Specifies the size, in TCHARs, of the buffer pointed to by lpstrFile. For the ANSI version, this is the number of bytes; for the Unicode version, this is the number of characters. The buffer must be large enough to store the path and file name string or strings, including the terminating NULL character. The GetOpenFileName and GetSaveFileName functions return FALSE if the buffer is too small to contain the file information. The buffer should be at least 256 characters long.

Why in the world use 21000? It says at least 256, but the MAX_PATH (on Windows XP) is 260. Why not make it that.

Or why not increase the size of the buffer (using the keyword new) while the GetOpenFileName function returns FALSE. You will have to check what error returns, you can do so with the CommDlgExtendedError function, you are looking for the FNERR_BUFFERTOOSMALL error code.

Chesso · Mar 10th, 2006, 3:47 PM

Why 21000? because it's just long enough for 100 files each with a character length of 100 plus the length of the directory and any additional spacing or added characters by me for easier parsing.

I already know I get the buffer to small error, It doesn't need any checking.

nnxion · Mar 10th, 2006, 4:40 PM

Sorry, I missed the multiple files part. Just increase the size of the buffer by catching the CDN_SELCHANGE Notification, which is received by your OFNHookProc hook procedure. Easy as Dell.

Chesso · Mar 10th, 2006, 4:46 PM

Sorry to be bothersome but if you have the time to make up an example for me it would be greatly appreciated. I'm used to handling all this stuff in Delphi and there's still quite a bit I haven't picked up yet.

nnxion · Mar 11th, 2006, 4:19 AM

Well I don't know if this works as I haven't tested fed it to the compiler and never done it before, but here goes anyway:

(Toggle Plain Text)

std::string OpenSaveDialog(int Open, char* InitDir)
{
	OPENFILENAME ofn;
	char * szFileName = NULL;
	string FData("");

	ZeroMemory(&ofn, sizeof(OPENFILENAME));
	ofn.lStructSize = sizeof(OPENFILENAME);
	ofn.hwndOwner = NULL;
	ofn.lpstrFile = szFileName;
	ofn.nMaxFile = 21000;
	ofn.lpfnHook = OFNHookProc;

	switch(Open)
	{
		case 0:
		break;

		case 1:
			ofn.lpstrFilter = "All Supported Files\0*.mp3;*.mp2;*.wav;*.wma;*.mid;*.ogg\0";
			ofn.lpstrInitialDir = InitDir;
			ofn.Flags = OFN_EXPLORER | OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_ALLOWMULTISELECT;

			if (GetOpenFileName(&ofn))
			{
				int len = strlen(ofn.lpstrFile);

				if( ofn.lpstrFile[len + 1] == 0)
				{
					return ofn.lpstrFile;
				} // If single file was selected.

				else
				{
					// This is the directory.
					FData = ofn.lpstrFile;

					ofn.lpstrFile += len + 1;
					while(ofn.lpstrFile[0])
					{
						// This will contain the current file name from multiple selection.
						FData = FData + "|" + ofn.lpstrFile;

						// Find next name
						len = strlen(ofn.lpstrFile);
						ofn.lpstrFile += len + 1;
					}
					return FData;
				}
			}

			else
			{
				return "CANCEL";
			}
		break;

		case 2:
			ofn.lpstrFilter = "All Supported Files\0*.sm3l;*.sm3;*.m3u;*.pls\0";
			ofn.lpstrInitialDir = InitDir;
			ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY;
			ofn.lpstrDefExt = "sm3l";

			if(GetOpenFileName(&ofn))
			{
				return ofn.lpstrFile;
			}

			else
			{
				return "CANCEL";
			}
		break;

		case 3:
			ofn.lpstrFilter = "SM3 format\0*.sm3\0M3U Format\0*.m3u\0PLS Format\0*.pls\0";
			ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
			ofn.lpstrDefExt = "sm3l";

			if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; }

			else
			{
				return "CANCEL";
			}
		break;
	}
}

UINT CALLBACK OFNHookProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam )
{
	UINT neededSize;
	switch(message)
	{
		case WM_INITDIALOG:
			if(!SetProp(GetParent(hDlg), "OFN", (void *)lParam))
			{
			  MessageBox(NULL, "SET PRop Failed", "ERROR", MB_OK);
			}
		break;

		case WM_NOTIFY:
			OFNOTIFY* lpof = (OFNOTIFY*)lParam;

			if(lpof->hdr.code == CDN_SELCHANGE)
			{
				neededSize = CommDlg_OpenSave_GetSpec(GetParent(hDlg), NULL, 0);
				neededSize += MAX_PATH;

				pOfn = (LPOPENFILENAME)GetProp(GetParent(hDlg), "OFN");
				if(pOfn->nMaxFile < neededSize)
				{
					if(pOfn->lpstrFile == NULL)
					{
						pOfn->lpstrFile = (LPTSTR)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, neededSize);
					}

					else
					{
						pOfn->lpstrFile = (LPTSTR)HeapReAlloc(GetProcessHeap(), 0, pOfn->lpstrFile, neededSize);
					}

					if(pOfn->lpstrFile != NULL)
					{
							pOfn->lpstrFile[0] = '\0';
							pOfn->nMaxFile  = neededSize;
					}
				}
			}
		break;

		case WM_DESTROY:
			RemoveProp(GetParent(hDlg), "OFN");
		break;
		}
	}
	return 0;
}

std::string OpenSaveDialog(int Open, char* InitDir)
{
	OPENFILENAME ofn;
	char * szFileName = NULL;
	string FData("");

	ZeroMemory(&ofn, sizeof(OPENFILENAME));
	ofn.lStructSize = sizeof(OPENFILENAME);
	ofn.hwndOwner = NULL;
	ofn.lpstrFile = szFileName;
	ofn.nMaxFile = 21000;
	ofn.lpfnHook = OFNHookProc;

	switch(Open)
	{
		case 0:
		break;

		case 1:
			ofn.lpstrFilter = "All Supported Files\0*.mp3;*.mp2;*.wav;*.wma;*.mid;*.ogg\0";
			ofn.lpstrInitialDir = InitDir;
			ofn.Flags = OFN_EXPLORER | OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_ALLOWMULTISELECT;

			if (GetOpenFileName(&ofn))
			{
				int len = strlen(ofn.lpstrFile);

				if( ofn.lpstrFile[len + 1] == 0)
				{
					return ofn.lpstrFile;
				} // If single file was selected.

				else
				{
					// This is the directory.
					FData = ofn.lpstrFile;

					ofn.lpstrFile += len + 1;
					while(ofn.lpstrFile[0])
					{
						// This will contain the current file name from multiple selection.
						FData = FData + "|" + ofn.lpstrFile;

						// Find next name
						len = strlen(ofn.lpstrFile);
						ofn.lpstrFile += len + 1;
					}
					return FData;
				}
			}

			else
			{
				return "CANCEL";
			}
		break;

		case 2:
			ofn.lpstrFilter = "All Supported Files\0*.sm3l;*.sm3;*.m3u;*.pls\0";
			ofn.lpstrInitialDir = InitDir;
			ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY;
			ofn.lpstrDefExt = "sm3l";

			if(GetOpenFileName(&ofn))
			{
				return ofn.lpstrFile;
			}

			else
			{
				return "CANCEL";
			}
		break;

		case 3:
			ofn.lpstrFilter = "SM3 format\0*.sm3\0M3U Format\0*.m3u\0PLS Format\0*.pls\0";
			ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
			ofn.lpstrDefExt = "sm3l";

			if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; }

			else
			{
				return "CANCEL";
			}
		break;
	}
}

UINT CALLBACK OFNHookProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam )
{
	UINT neededSize;
	switch(message)
	{
		case WM_INITDIALOG:
			if(!SetProp(GetParent(hDlg), "OFN", (void *)lParam))
			{
			  MessageBox(NULL, "SET PRop Failed", "ERROR", MB_OK);
			}
		break;

		case WM_NOTIFY:
			OFNOTIFY* lpof = (OFNOTIFY*)lParam;

			if(lpof->hdr.code == CDN_SELCHANGE)
			{
				neededSize = CommDlg_OpenSave_GetSpec(GetParent(hDlg), NULL, 0);
				neededSize += MAX_PATH;

				pOfn = (LPOPENFILENAME)GetProp(GetParent(hDlg), "OFN");
				if(pOfn->nMaxFile < neededSize)
				{
					if(pOfn->lpstrFile == NULL)
					{
						pOfn->lpstrFile = (LPTSTR)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, neededSize);
					}

					else
					{
						pOfn->lpstrFile = (LPTSTR)HeapReAlloc(GetProcessHeap(), 0, pOfn->lpstrFile, neededSize);
					}

					if(pOfn->lpstrFile != NULL)
					{
							pOfn->lpstrFile[0] = '\0';
							pOfn->nMaxFile  = neededSize;
					}
				}
			}
		break;

		case WM_DESTROY:
			RemoveProp(GetParent(hDlg), "OFN");
		break;
		}
	}
	return 0;
}

Hopes that helps you.

Chesso · Mar 11th, 2006, 5:08 AM

Dev-CPP is giving me quite a few compile errors.....

OFNHookProc Undeclared(first use this function)
`pOfn` undeclared(first use this function)
jump to case label
crosses initalization of `OFNOTIFY*lpof`

Err yeah there's more but Iv'e never had alot of these errors so i'm clueless.

EDIT: Putting the OFNHookProc above my function gets rid of a couple of errors but most remain.

Cache · Mar 11th, 2006, 6:58 AM

Quote:

Originally Posted by Chesso

Putting the OFNHookProc above my function gets rid of a couple of errors but most remain.

Or you could put the function prototype at the top of the file.

Quote:

`pOfn` undeclared(first use this function)

The value being assigned to pOfn is cast as type LPOPENFILENAME. So I assume the following will solve that issue:

(Toggle Plain Text)

LPOPENFILENAME pOfn = (LPOPENFILENAME)GetProp(GetParent(hDlg), "OFN");

Quote:

jump to case label
crosses initalization of `OFNOTIFY*lpof`

The WM_NOTIFY case in OFNHookProc initializes new variables, so it should be enclosed in curly braces. There is also a superfluous brace.

Chesso · Mar 11th, 2006, 9:47 AM

I still can't seem to get it to compile without complaining about alot of stuff.

This is a DLL not a normal Win32 application, there's no windows or anything like that created so the DLL doesn't really have a handle I suppose....

The two functions in this DLL aren't defined at the top of the file or anything, there just in my .h file for exporting.

And i'm just going to say this again but the only experience I have with C++ is writing extremely basic DLL's and a base Win32 GUI. Everything else iv'e done in either Visual Basic or for the last year and a half Borland Delphi.

Mar 10th, 2006, 8:11 AM	#1
Chesso Newbie Join Date: Mar 2006 Posts: 7 Rep Power: 0	Problem with GetOpenFileName buffer too small. I have written a DLL for a Delphi application I am making and decided to have the Open/Save dialog functionality within an external DLL instead of inside the application. The problem is I have to hard code the buffer which makes the DLL much larger then it should be. I have read on MSDN about this problem but it really does not help as I am not too proficient with C++ in general as I only use it when I need it. I have found plenty of article about this issue but they only explain how to solve it using MFC with VS. I am however using Dev-CPP enviroment. Here is the function source: (Toggle Plain Text) std::string OpenSaveDialog(int Open, char* InitDir) { OPENFILENAME ofn; char szFileName[21000] = ""; string FData(""); ZeroMemory(&ofn, sizeof(OPENFILENAME)); ofn.lStructSize = sizeof(OPENFILENAME); ofn.hwndOwner = NULL; ofn.lpstrFile = szFileName; ofn.nMaxFile = 21000; switch(Open) { case 0: break; case 1: ofn.lpstrFilter = "All Supported Files\0.mp3;.mp2;.wav;.wma;.mid;.ogg\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_FILEMUSTEXIST \| OFN_HIDEREADONLY \| OFN_ALLOWMULTISELECT; if (GetOpenFileName(&ofn)) { int len = strlen(ofn.lpstrFile); if( ofn.lpstrFile[len + 1] == 0) { return ofn.lpstrFile; } // If single file was selected. else { // This is the directory. FData = ofn.lpstrFile; ofn.lpstrFile += len + 1; while(ofn.lpstrFile[0]) { // This will contain the current file name from multiple selection. FData = FData + "\|" + ofn.lpstrFile; // Find next name len = strlen(ofn.lpstrFile); ofn.lpstrFile += len + 1; } return FData; } } else { return "CANCEL"; } break; case 2: ofn.lpstrFilter = "All Supported Files\0.sm3l;.sm3;.m3u;.pls\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY; ofn.lpstrDefExt = "sm3l"; if (GetOpenFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; case 3: ofn.lpstrFilter = "SM3 format\0.sm3\0M3U Format\0.m3u\0PLS Format\0.pls\0"; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY \| OFN_OVERWRITEPROMPT; ofn.lpstrDefExt = "sm3l"; if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } } } std::string OpenSaveDialog(int Open, char InitDir) { OPENFILENAME ofn; char szFileName[21000] = ""; string FData(""); ZeroMemory(&ofn, sizeof(OPENFILENAME)); ofn.lStructSize = sizeof(OPENFILENAME); ofn.hwndOwner = NULL; ofn.lpstrFile = szFileName; ofn.nMaxFile = 21000; switch(Open) { case 0: break; case 1: ofn.lpstrFilter = "All Supported Files\0.mp3;.mp2;.wav;.wma;.mid;.ogg\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_FILEMUSTEXIST \| OFN_HIDEREADONLY \| OFN_ALLOWMULTISELECT; if (GetOpenFileName(&ofn)) { int len = strlen(ofn.lpstrFile); if( ofn.lpstrFile[len + 1] == 0) { return ofn.lpstrFile; } // If single file was selected. else { // This is the directory. FData = ofn.lpstrFile; ofn.lpstrFile += len + 1; while(ofn.lpstrFile[0]) { // This will contain the current file name from multiple selection. FData = FData + "\|" + ofn.lpstrFile; // Find next name len = strlen(ofn.lpstrFile); ofn.lpstrFile += len + 1; } return FData; } } else { return "CANCEL"; } break; case 2: ofn.lpstrFilter = "All Supported Files\0.sm3l;.sm3;.m3u;.pls\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY; ofn.lpstrDefExt = "sm3l"; if (GetOpenFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; case 3: ofn.lpstrFilter = "SM3 format\0.sm3\0M3U Format\0.m3u\0PLS Format\0*.pls\0"; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY \| OFN_OVERWRITEPROMPT; ofn.lpstrDefExt = "sm3l"; if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } } } Does anyone know how to solve this issue? From what I read on MSDN I need some sort of callback function to resize the buffer if necessary and read something about calling it twice.....

Mar 10th, 2006, 4:40 PM	#4
nnxion Programming Guru Join Date: Jun 2005 Location: elemental plane Posts: 1,429 Rep Power: 5	Sorry, I missed the multiple files part. Just increase the size of the buffer by catching the CDN_SELCHANGE Notification, which is received by your OFNHookProc hook procedure. Easy as Dell. __________________ "Employ your time in improving yourself by other men's writings, so that you shall gain easily what others have labored hard for." -- Socrates

Mar 11th, 2006, 4:19 AM	#6
nnxion Programming Guru Join Date: Jun 2005 Location: elemental plane Posts: 1,429 Rep Power: 5	Well I don't know if this works as I haven't tested fed it to the compiler and never done it before, but here goes anyway: (Toggle Plain Text) std::string OpenSaveDialog(int Open, char* InitDir) { OPENFILENAME ofn; char * szFileName = NULL; string FData(""); ZeroMemory(&ofn, sizeof(OPENFILENAME)); ofn.lStructSize = sizeof(OPENFILENAME); ofn.hwndOwner = NULL; ofn.lpstrFile = szFileName; ofn.nMaxFile = 21000; ofn.lpfnHook = OFNHookProc; switch(Open) { case 0: break; case 1: ofn.lpstrFilter = "All Supported Files\0.mp3;.mp2;.wav;.wma;.mid;.ogg\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_FILEMUSTEXIST \| OFN_HIDEREADONLY \| OFN_ALLOWMULTISELECT; if (GetOpenFileName(&ofn)) { int len = strlen(ofn.lpstrFile); if( ofn.lpstrFile[len + 1] == 0) { return ofn.lpstrFile; } // If single file was selected. else { // This is the directory. FData = ofn.lpstrFile; ofn.lpstrFile += len + 1; while(ofn.lpstrFile[0]) { // This will contain the current file name from multiple selection. FData = FData + "\|" + ofn.lpstrFile; // Find next name len = strlen(ofn.lpstrFile); ofn.lpstrFile += len + 1; } return FData; } } else { return "CANCEL"; } break; case 2: ofn.lpstrFilter = "All Supported Files\0.sm3l;.sm3;.m3u;.pls\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY; ofn.lpstrDefExt = "sm3l"; if(GetOpenFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; case 3: ofn.lpstrFilter = "SM3 format\0.sm3\0M3U Format\0.m3u\0PLS Format\0.pls\0"; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY \| OFN_OVERWRITEPROMPT; ofn.lpstrDefExt = "sm3l"; if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; } } UINT CALLBACK OFNHookProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam ) { UINT neededSize; switch(message) { case WM_INITDIALOG: if(!SetProp(GetParent(hDlg), "OFN", (void )lParam)) { MessageBox(NULL, "SET PRop Failed", "ERROR", MB_OK); } break; case WM_NOTIFY: OFNOTIFY* lpof = (OFNOTIFY)lParam; if(lpof->hdr.code == CDN_SELCHANGE) { neededSize = CommDlg_OpenSave_GetSpec(GetParent(hDlg), NULL, 0); neededSize += MAX_PATH; pOfn = (LPOPENFILENAME)GetProp(GetParent(hDlg), "OFN"); if(pOfn->nMaxFile < neededSize) { if(pOfn->lpstrFile == NULL) { pOfn->lpstrFile = (LPTSTR)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, neededSize); } else { pOfn->lpstrFile = (LPTSTR)HeapReAlloc(GetProcessHeap(), 0, pOfn->lpstrFile, neededSize); } if(pOfn->lpstrFile != NULL) { pOfn->lpstrFile[0] = '\0'; pOfn->nMaxFile = neededSize; } } } break; case WM_DESTROY: RemoveProp(GetParent(hDlg), "OFN"); break; } } return 0; } std::string OpenSaveDialog(int Open, char InitDir) { OPENFILENAME ofn; char * szFileName = NULL; string FData(""); ZeroMemory(&ofn, sizeof(OPENFILENAME)); ofn.lStructSize = sizeof(OPENFILENAME); ofn.hwndOwner = NULL; ofn.lpstrFile = szFileName; ofn.nMaxFile = 21000; ofn.lpfnHook = OFNHookProc; switch(Open) { case 0: break; case 1: ofn.lpstrFilter = "All Supported Files\0.mp3;.mp2;.wav;.wma;.mid;.ogg\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_FILEMUSTEXIST \| OFN_HIDEREADONLY \| OFN_ALLOWMULTISELECT; if (GetOpenFileName(&ofn)) { int len = strlen(ofn.lpstrFile); if( ofn.lpstrFile[len + 1] == 0) { return ofn.lpstrFile; } // If single file was selected. else { // This is the directory. FData = ofn.lpstrFile; ofn.lpstrFile += len + 1; while(ofn.lpstrFile[0]) { // This will contain the current file name from multiple selection. FData = FData + "\|" + ofn.lpstrFile; // Find next name len = strlen(ofn.lpstrFile); ofn.lpstrFile += len + 1; } return FData; } } else { return "CANCEL"; } break; case 2: ofn.lpstrFilter = "All Supported Files\0.sm3l;.sm3;.m3u;.pls\0"; ofn.lpstrInitialDir = InitDir; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY; ofn.lpstrDefExt = "sm3l"; if(GetOpenFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; case 3: ofn.lpstrFilter = "SM3 format\0.sm3\0M3U Format\0.m3u\0PLS Format\0.pls\0"; ofn.Flags = OFN_EXPLORER \| OFN_PATHMUSTEXIST \| OFN_HIDEREADONLY \| OFN_OVERWRITEPROMPT; ofn.lpstrDefExt = "sm3l"; if (GetSaveFileName(&ofn)) { return ofn.lpstrFile; } else { return "CANCEL"; } break; } } UINT CALLBACK OFNHookProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam ) { UINT neededSize; switch(message) { case WM_INITDIALOG: if(!SetProp(GetParent(hDlg), "OFN", (void )lParam)) { MessageBox(NULL, "SET PRop Failed", "ERROR", MB_OK); } break; case WM_NOTIFY: OFNOTIFY* lpof = (OFNOTIFY*)lParam; if(lpof->hdr.code == CDN_SELCHANGE) { neededSize = CommDlg_OpenSave_GetSpec(GetParent(hDlg), NULL, 0); neededSize += MAX_PATH; pOfn = (LPOPENFILENAME)GetProp(GetParent(hDlg), "OFN"); if(pOfn->nMaxFile < neededSize) { if(pOfn->lpstrFile == NULL) { pOfn->lpstrFile = (LPTSTR)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, neededSize); } else { pOfn->lpstrFile = (LPTSTR)HeapReAlloc(GetProcessHeap(), 0, pOfn->lpstrFile, neededSize); } if(pOfn->lpstrFile != NULL) { pOfn->lpstrFile[0] = '\0'; pOfn->nMaxFile = neededSize; } } } break; case WM_DESTROY: RemoveProp(GetParent(hDlg), "OFN"); break; } } return 0; } Hopes that helps you. __________________ "Employ your time in improving yourself by other men's writings, so that you shall gain easily what others have labored hard for." -- Socrates

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Mar 10th, 2006, 3:47 PM	#3
Chesso Newbie Join Date: Mar 2006 Posts: 7 Rep Power: 0	Why 21000? because it's just long enough for 100 files each with a character length of 100 plus the length of the directory and any additional spacing or added characters by me for easier parsing. I already know I get the buffer to small error, It doesn't need any checking.

Mar 10th, 2006, 4:46 PM	#5
Chesso Newbie Join Date: Mar 2006 Posts: 7 Rep Power: 0	Sorry to be bothersome but if you have the time to make up an example for me it would be greatly appreciated. I'm used to handling all this stuff in Delphi and there's still quite a bit I haven't picked up yet.

Mar 11th, 2006, 5:08 AM	#7
Chesso Newbie Join Date: Mar 2006 Posts: 7 Rep Power: 0	Dev-CPP is giving me quite a few compile errors..... OFNHookProc Undeclared(first use this function) `pOfn` undeclared(first use this function) jump to case label crosses initalization of `OFNOTIFY*lpof` Err yeah there's more but Iv'e never had alot of these errors so i'm clueless. EDIT: Putting the OFNHookProc above my function gets rid of a couple of errors but most remain.

Mar 11th, 2006, 9:47 AM	#9
Chesso Newbie Join Date: Mar 2006 Posts: 7 Rep Power: 0	I still can't seem to get it to compile without complaining about alot of stuff. This is a DLL not a normal Win32 application, there's no windows or anything like that created so the DLL doesn't really have a handle I suppose.... The two functions in this DLL aren't defined at the top of the file or anything, there just in my .h file for exporting. And i'm just going to say this again but the only experience I have with C++ is writing extremely basic DLL's and a base Win32 GUI. Everything else iv'e done in either Visual Basic or for the last year and a half Borland Delphi.

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Problem with GetOpenFileName buffer too small.