What are the Win32 APIs to use to programically delete files and folders?
Edit
DeleteFile and RemoveDirectory are what I was looking for.
However, for this project I ended up using SHFileOperation.
I found the sample code at CodeGuru helpful.
There are two ways to approach this. One is through the File Services (using commands such as DeleteFile and RemoveDirectory) and the other is through the Windows Shell (using SHFileOperation). The latter is recommended if you want to delete non-empty directories or if you want explorer style feedback (progress dialogs with flying files, for example). The quickest way of doing this is to create a SHFILEOPSTRUCT, initialise it and call SHFileOperation, thus:
void silently_remove_directory(LPCTSTR dir) // Fully qualified name of the directory being deleted, without trailing backslash
{
SHFILEOPSTRUCT file_op = {
NULL,
FO_DELETE,
dir,
"",
FOF_NOCONFIRMATION |
FOF_NOERRORUI |
FOF_SILENT,
false,
0,
"" };
SHFileOperation(&file_op);
}
This silently deletes the entire directory. You can add feedback and prompts by varying the SHFILEOPSTRUCT initialisation - do read up on it.
I think you want DeleteFile and RemoveDirectory
See uvgroovy's comment above. You need 2 nulls at the end of the 'dir' field.
int silently_remove_directory(LPCTSTR dir) // Fully qualified name of the directory being deleted, without trailing backslash
{
int len = strlen(dir) + 2; // required to set 2 nulls at end of argument to SHFileOperation.
char* tempdir = (char*) malloc(len);
memset(tempdir,0,len);
strcpy(tempdir,dir);
SHFILEOPSTRUCT file_op = {
NULL,
FO_DELETE,
tempdir,
NULL,
FOF_NOCONFIRMATION |
FOF_NOERRORUI |
FOF_SILENT,
false,
0,
"" };
int ret = SHFileOperation(&file_op);
free(tempdir);
return ret; // returns 0 on success, non zero on failure.
}
I believe DeleteFile does not send the file to the Recycle Bin. Also, RemoveDirectory removes only empty dirs. SHFileOperation would give you the most control over what and how to delete and would show the standard Windows UI dialog boxes (e.g. "Preparing to delete etc.) if needed.
/* function used to send files and folder to recycle bin in win32 */
int fn_Send_Item_To_RecycleBin(TCHAR newpath[])
{
_tcscat_s(newpath, MAX_PATH,_T("|"));
TCHAR* Lastptr = _tcsrchr(newpath, _T('|'));
*Lastptr = _T('\0'); // Replace last pointer with Null for double null termination
SHFILEOPSTRUCT shFileStruct;
ZeroMemory(&shFileStruct,sizeof(shFileStruct));
shFileStruct.hwnd=NULL;
shFileStruct.wFunc= FO_DELETE;
shFileStruct.pFrom= newpath;
shFileStruct.fFlags = FOF_ALLOWUNDO | FOF_NOCONFIRMATION | FOF_NOERRORUI | FOF_SILENT;
return SHFileOperation(&shFileStruct);
}
For C++ programming, if you're willing to work with third-party libraries,
boost::filesystem::remove_all(yourPath)
is much simpler than SHFileOperation.
Related
I use this code to delete a file from my local system:
bool Delete(const ::CComPtr<IShellItem>& pShellItem, bool permanently)
{
::CComPtr<IFileOperation> pFileOperation;
// initialize the file operation
HRESULT hr = ::CoCreateInstance(CLSID_FileOperation, NULL, CLSCTX_ALL, IID_PPV_ARGS(&pFileOperation));
if (FAILED(hr))
return false;
// don't show any system error message to user, but returns an error code if delete failed. Also show elevation prompt if required
DWORD fileOpFlags = FOF_SILENT | FOF_NO_UI | FOF_NOERRORUI | FOF_NOCONFIRMATION | FOFX_EARLYFAILURE | FOFX_SHOWELEVATIONPROMPT;
// do move file on Recycle Bin instead of deleting it permanently?
if (!permanently)
if (WOSHelper_MSWindows::GetWindowsVersion() >= WOSHelper_MSWindows::IEVersion::IE_Win8)
// Windows 8 introduces the FOFX_RECYCLEONDELETE flag and deprecates the FOF_ALLOWUNDO in favor of FOFX_ADDUNDORECORD
fileOpFlags |= FOFX_ADDUNDORECORD | FOFX_RECYCLEONDELETE;
else
// for Windows 7 and Vista, RecycleOnDelete is the default behavior
fileOpFlags |= FOF_ALLOWUNDO;
// prepare the delete operation flags
hr = pFileOperation->SetOperationFlags(fileOpFlags);
if (FAILED(hr))
return false;
// mark item for deletion
hr = pFileOperation->DeleteItem(pShellItem, nullptr);
if (FAILED(hr))
return false;
// delete the item
hr = pFileOperation->PerformOperations();
if (FAILED(hr))
return false;
return true;
}
On my local computer I also mounted an alias disk using this command:
subst V: "C:\MyData"
Now, using my above alias, I need to move a file to the Recycle Bin (this is done by setting the permanently parameter to false while I call my function) from the following path:
V:\MyProject\MyFileToDel.txt
Doing that, the file is well deleted from its containing folder, but it is never moved to the Recycle Bin. On the other hand, when I try to delete my file from its original path:
C:\MyData\MyProject\MyFileToDel.txt
The file is well deleted from its containing folder AND moved to the Recycle Bin, as expected.
However this is the exact same file in the exact same location in the both cases, the only difference is that one is deleted from an alias, and the other from its complete path.
What should I change to make the function to work in the both cases?
I have the following code that tries to read a INI file from a given location and if it fails it then tries to open in the current directory. My application has these two modes of execution, MAM and No MAM, hence the variable names.
{
const char section[]="CONFIG";
const char key[]="HEAP";
char value[16];
const char pwcfgFileMam[]="..\\pwcfg.ini";
const char * const pwcfgFileNoMam = pwcfgFileMam + 1;
long rc;
DWORD rcProfile;
value[0] = '\0';
rcProfile= GetPrivateProfileString( section, key, "", value,
sizeof(value)-1, pwcfgFileMam );
if ( 0 == rcProfile )
{
rcProfile = GetPrivateProfileString( section, key, "", value,
sizeof(value)-1, pwcfgFileNoMam );
}
// DO_SOMETHING(value);
}
According to the official documentation, the function should work only with full paths which is another name for absolute paths, but this snippet work as long as you put a .\ or ..\ prefix on the path. I previously had a bug in the 6th line, it was coded like this:
const char * const pwcfgFileNoMam = pwcfgFileMam + 3;
So, the function cannot work probably with only filenames, it needs at least a . or .. to "find" the file. My boss told me that the function runs in another process or context or something, and thus it needs the "path" to force this other context to query the requirer for its current working directory. Anyone has a more throughly answer on why this function behaves like this? Is this just the case of a badly implemented and badly documented API?
Oh, by the way, I'm compiling this code with Visual Studio 2008 on a Windows 7 machine.
I am trying to delete all the temporary files created by my application during uninstall. I use the following code:
bool DeleteFileNow( QString filenameStr )
{
wchar_t* filename;
filenameStr.toWCharArray(filename);
QFileInfo info(filenameStr);
// don't do anything if the file doesn't exist!
if (!info.exists())
return false;
// determine the path in which to store the temp filename
wchar_t* path;
info.absolutePath().toWCharArray(path);
TRACE( "Generating temporary name" );
// generate a guaranteed to be unique temporary filename to house the pending delete
wchar_t tempname[MAX_PATH];
if (!GetTempFileNameW(path, L".xX", 0, tempname))
return false;
TRACE( "Moving real file name to dummy" );
// move the real file to the dummy filename
if (!MoveFileExW(filename, tempname, MOVEFILE_REPLACE_EXISTING))
{
// clean up the temp file
DeleteFileW(tempname);
return false;
}
TRACE( "Queueing the OS" );
// queue the deletion (the OS will delete it when all handles (ours or other processes) close)
return DeleteFileW(tempname) != FALSE;
}
My application is crashing. I think its due to some missing windows dll for the operations performed. Is there any other way to perform the same operation using Qt alone?
Roku have already told your problem in manipulating with QString and wchar_t*.
See the documentation: QString Class Reference, method toWCharArray:
int QString::toWCharArray ( wchar_t * array ) const
Fills the array with the data contained in this QString object. The array is encoded in utf16 on platforms where wchar_t is 2 bytes wide (e.g. windows) and in ucs4 on platforms where wchar_t is 4 bytes wide (most Unix systems).
array has to be allocated by the caller and contain enough space to hold the complete string (allocating the array with the same length as the string is always sufficient).
returns the actual length of the string in array.
If you are simply looking for a way to remove a file using Qt, use QFile::remove:
QFile file(fileNameStr);
file.remove(); // Returns a bool; true if successful
If you want Qt to manage the entire life cycle of a temporary file for you, take a look at QTemporaryFile:
QTemporaryFile tempFile(fileName);
if (tempFile.open())
{
// Do stuff with file here
}
// When tempFile falls out of scope, it is automatically deleted.
I am a new member and joined this site after referring to it loads of times when i was stuck with some programming problems. I am trying to code a media player (Win32 SDK VC++ 6.0) for my college project and I am stuck. I have searched on various forums and msdn and finally landed on the function GetShortPathName which enables me to play through folders and files which have a whitespace in their names. I will paste the code here so it will be much more clearer as to what i am trying to do.
case IDM_FILE_OPEN :
ZeroMemory(&ofn, sizeof(ofn));
ofn.lStructSize = sizeof(ofn);
ofn.hwndOwner = hwnd;
ofn.lpstrFilter = "Media Files (All Supported Types)\0*.avi;*.mpg;*.mpeg;*.asf;*.wmv;*.mp2;*.mp3\0"
"Movie File (*.avi;*.mpg;*.mpeg)\0*.avi;*.mpg;*.mpeg\0"
"Windows Media File (*.asf;*.wmv)\0*.asf;*.wmv\0"
"Audio File (*.mp2;*.mp3)\0*.mp2;*.mp3\0"
"All Files(*.*)\0*.*\0";
ofn.lpstrFile = szFileName;
ofn.nMaxFile = MAX_PATH;
ofn.Flags = OFN_EXPLORER | OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_ALLOWMULTISELECT | OFN_CREATEPROMPT;
ofn.lpstrDefExt = "mp3";
if(GetOpenFileName(&ofn))
{
length = GetShortPathName(szFileName, NULL, 0);
buffer = (TCHAR *) malloc (sizeof(length));
length = GetShortPathName(szFileName, buffer, length);
for(i = 0 ; i < MAX_PATH ; i++)
{
if(buffer[i] == '\\')
buffer[i] = '/';
}
SendMessage(hList,LB_ADDSTRING,0,(LPARAM)buffer);
mciSendString("open buffer alias myFile", NULL, 0, NULL);
mciSendString("play buffer", NULL, 0, NULL);
}
return 0;
using the GetShortPathName function i get the path as : D:/Mp3z/DEEPBL~1/03SLEE~1.mp3
Putting this path directly in Play button case
mciSendString("open D:/Mp3jh/DEEPBL~1/03SLEE~1.mp3 alias myFile", NULL, 0, NULL);
mciSendString("play myFile", NULL, 0, NULL);
the file opens and plays fine. But as soon as i try to open and play it through the open file dialog box, nothing happens. Any input appreciated.
It looks like the problem is that you're passing the name of the buffer variable to the mciSendString function as a string, rather than passing the contents of the buffer.
You need to concatenate the arguments you want to pass (open and alias myFile) with the contents of buffer.
The code can also be much simplified by replacing malloc with an automatic array. You don't need to malloc it because you don't need it outside of the block scope. (And you shouldn't be using malloc in C++ code anyway; use new[] instead.)
Here's a modified snippet of the code shown in your question:
(Warning: changes made using only my eyes as a compiler! Handle with care.)
if(GetOpenFileName(&ofn))
{
// Get the short path name, and place it in the buffer array.
// We know that a short path won't be any longer than MAX_PATH, so we can
// simply allocate a statically-sized array without futzing with new[].
//
// Note: In production code, you should probably check the return value
// of the GetShortPathName function to make sure it succeeded.
TCHAR buffer[MAX_PATH];
GetShortPathName(szFileName, buffer, MAX_PATH);
// Add the short path name to your ListBox control.
//
// Note: In C++ code, you should probably use C++-style casts like
// reinterpret_cast, rather than C-style casts!
SendMessage(hList, LB_ADDSTRING, 0, reinterpret_cast<LPARAM>(buffer));
// Build the argument string to pass to the mciSendString function.
//
// Note: In production code, you probably want to use the more secure
// alternatives to the string concatenation functions.
// See the documentation for more details.
// And, as before, you should probably check return values for error codes.
TCHAR arguments[MAX_PATH * 2]; // this will definitely be large enough
lstrcat(arguments, TEXT("open"));
lstrcat(arguments, buffer);
lstrcat(arguments, TEXT("alias myFile"));
// Or, better yet, use a string formatting function, like StringCbPrintf:
// StringCbPrintf(arguments, MAX_PATH * 2, TEXT("open %s alias myFile"),
// buffer);
// Call the mciSendString function with the argument string we just built.
mciSendString(arguments, NULL, 0, NULL);
mciSendString("play myFile", NULL, 0, NULL);
}
Do note that, as the above code shows, working with C-style strings (character arrays) is a real pain in the ass. C++ provides a better alternative, in the form of the std::string class. You should strongly consider using that instead. To call Windows API functions, you'll still need a C-style string, but you can get one of those by using the c_str method of the std::string class.
I'm having an issue with using SHGetFileInfo on the public desktop and files in the public desktop. I'll focus on the actual desktop folder (CSIDL_COMMON_DESKTOPDIRECTORY or usually "C:\Users\Public\Desktop"). Also - I've started seeing this behavior only recently, but I can't pinpoint the exact change which made it faulty. The actual call to ShGetFileInfo has not changed (as far as I can tell).
So I have this (I've omitted intermediate error checks to shorten - the function calls return with success):
SHFILEINFOW info;
uint32_t return_value = 0;
uint32_t flags = SHGFI_TYPENAME|SHGFI_ICON|SHGFI_SMALLICON|SHGFI_SYSICONINDEX;
uint32_t attributes = FILE_ATTRIBUTE_NORMAL;
wchar_t *path = L"C:\\Users\\Public\\Desktop";
return_value = SHGetFileInfoW(path, attributes, &info, sizeof(SHFILEINFOW), flags);
printf("[%ls] %u ", path, return_value);
This returns 0 as the return value. If I populate path using:
SHGetFolderPathW(NULL, CSIDL_COMMON_DESKTOPDIRECTORY, NULL, 0, path)
I get the same result. But if I use the pidl, as in:
LPITEMIDLIST pidl = NULL;
SHGetSpecialFolderLocation(NULL, CSIDL_COMMON_DESKTOPDIRECTORY, &pidl);
return_value = SHGetFileInfoW((LPCWSTR) pidl, attributes, &info, sizeof(SHFILEINFOW), flags | SHGFI_PIDL);
Then I get something which I expect, a handle to the system small icon list.
I can't tell what I'm doing wrong - and it only happens on this specific folder. I actually need icons for the items inside the directory, so using the pidl doesn't seem to be an option right now. Any ideas on what is the expected way to retrieve icons from the common desktop?
--
I should mention this behavior happens on Windows Vista - using the path populated by SHGetFolderPathW on XP works fine
I had the same problem. It can be fixed by calling the function CoInitialize from OLE32.DLL when the program starts.
CoInitialize(0);
return_value = SHGetFileInfoW(path, attributes, &info, sizeof(SHFILEINFOW), flags);