Using COM dll in a Qt project - c++

In vs c++ I used the following code to use some functions in a dll file that I don't have its header
#import "dll path"
HRESULT hr = CoInitialize(NULL);
if (hr==S_OK)
{cout<<"INITIALIZED\n";}
Trans_ATLLib::ITransCriptPtr Trans;
hr = Trans.CreateInstance(__uuidof(Trans_ATLLib::TransCript));
if (hr==S_OK)
{cout<<"INSTANCE CREATED\n";}
hr =Trans->EnableLastCharTashkeel(true);
if (hr==S_OK)
{cout<<"EnableLastCharTashkeel DONE\n";}
hr =Trans->EnableEmphaticLAM_RAA(true);
if (hr==S_OK)
{cout<<"EnableEmphaticLAM_RAA DONE\n";}
VARIANT_BOOL test;
test = Trans->SetText(arabic_string);
if (test==0)
{cout<<"error in setting the arabic sting\n";}
string result;
result = Trans->GetResult();
istringstream iss(result);
vector<string> phonemes;
copy(istream_iterator<string>(iss),istream_iterator<string>(),back_inserter<vector<string> >(phonemes));
return phonemes;
}
But I found that Qt doesn't use the same method.
Can any one help me in calling these functions in Qt?
Thanks in advance.

If you use c++ - do the same! Qt is a set of libraries, not a different programming language - call to winApi everywhere you need, but don't forget that it is not portable.

Related

How to get the directory of the current DLL

I will build c-shared in golang -o config.dll.
Let's say the directory is c:\test\config.dll
In mail.dll, I'm going to open a configuration file.
This file is in the directory of config.dll.
c:\test\config.json
I'm calling it in c++ c:\test\c++.dll.
In c++ I use
{ // NB: XP+ solution!
HMODULE hModule = NULL;
GetModuleHandleEx(
GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
(LPCTSTR)GetCurrentModule,
&hModule);
return hModule;
}
WCHAR path3[MAX_PATH + 1] = { 0 };
HMODULE hm = GetCurrentModule();
::GetModuleFileName(hm, path3, MAX_PATH);
PathRemoveFileSpec(path3);
// path3 c:\test\c++.dll
What is the equivalent of this in Go?
I try to use
os.Getwd()
runtime.Caller(1)
os.Args[0]
os.Executable()
I want to get directory c:\test\
You can use cgo to call the same function in whatever library it exists.

Is there a new replacement for SHGetSpecialFolderLocation?

My app is written in C++Builder for Win32. My code uses the SHGetSpecialFolderLocation() API to get the CSIDL_APPDATA and CSIDL_MYDOCUMENTS paths.
I noticed on Microsoft's website dated 12/04/2018 that it says:
[SHGetSpecialFolderLocation is not supported and may be altered or unavailable in the future. Instead, use SHGetFolderLocation.]
Then for SHGetFolderLocation it says:
Deprecated
What is the current way to get these two paths?
My current code is below.
LPITEMIDLIST List = NULL;
wchar_t wPath[MAX_PATH + 1];
UnicodeString S01, Fi;
if( !SHGetSpecialFolderLocation(0, CSIDL_APPDATA, &List) ){
if( SHGetPathFromIDListW(List, wPath ) ){
S01 = wPath;
Fi = (S01+"\\my_files\\");
Form1->MyRoamingPath_Mh = Fi;
}
}
SHGetSpecialFolderLocation() was first introduced in Windws 95/NT4. It was deprecated in Windows 2000/XP in favor of SHGetFolderLocation() (which returns a folder location as an IDLIST_ABSOLUTE) and SHGetFolderPath() (which returns a folder location as a path string).
So, in your example, you could have used SHGetFolderPath() instead:
#include <Shlobj.h>
#include <SysUtils.hpp>
wchar_t wPath[MAX_PATH + 1];
if (SHGetFolderPathW(NULL, CSIDL_APPDATA, NULL, SHGFP_TYPE_CURRENT, wPath) == S_OK)
{
Form1->MyRoamingPath_Mh = IncludeTrailingPathDelimiter(wPath) + L"my_files\\";
}
In Vista, use of CSIDL was deprecated in favor of KNOWNFOLDERID. The above functions have been deprecated in favor of SHGetKnownFolderIDList()/IKnownFolder::GetIDList() and SHGetKnownFolderPath()/IKnownFolder::GetPath(), respectively.
This is actually stated at the bottom of the SHGetFolderLocation() documentation 1:
1: I guess you did not scroll down far enough to see it.
Note As of Windows Vista, this function is merely a wrapper for SHGetKnownFolderIDList. The CSIDL value is translated to its associated KNOWNFOLDERID and SHGetKnownFolderIDList is called. New applications should use the known folder system rather than the older CSIDL system, which is supported only for backward compatibility.
So, in your example, you can now use SHGetKnownFolderPath() instead:
#include <Shlobj.h>
#include <SysUtils.hpp>
PWSTR pwPath;
if (SHGetKnownFolderPath(FOLDERID_RoamingAppData, KF_FLAG_DEFAULT, NULL, &pwPath) == S_OK)
{
try
{
Form1->MyRoamingPath_Mh = IncludeTrailingPathDelimiter(pwPath) + L"my_files\\";
}
__finally
{
CoTaskMemFree(pwPath);
}
}
For the "My Documents" folder, use FOLDERID_Documents.

How to get Windows path using Qt/C++

I am trying to get the windows path using Qt and C++. The below code compiles, but not gettting the windows folder path in Qt. The same code works in Visual Studio 2010
wchar_t path[MAX_PATH];
SHGetFolderPath(NULL, CSIDL_WINDOWS, NULL, 0, path);
The below code change seems working:
int const bufferSize = 512;
QScopedPointer<WCHAR> dirPath(new WCHAR[bufferSize]);
ZeroMemory( dirPath.operator ->(), bufferSize);
SHGetFolderPath(NULL, CSIDL_WINDOWS, NULL, 0, dirPath.operator ->());
There isn't a Qt function to do this, but what you are asking could be achieved by reading the environtment variable WINDIR:
QStringList env_list(QProcess::systemEnvironment());
int idx = env_list.indexOf(QRegExp("^WINDIR=.*", Qt::CaseInsensitive));
if (idx > -1)
{
QStringList windir = env_list[idx].split('=');
qDebug() << "Var : " << windir[0];
qDebug() << "Path: " << windir[1];
}
Outputs:
Var : "WINDIR"
Path: "C:\WINDOWS"
QString windowsInstallPath;
#ifdef Q_WS_WIN
QDir d;
if (d.cd("%windir%"))
windowsInstallPath = d.absolutePath();
#endif
if (!windowsInstallPath.isNull())
qDebug() << windowsInstallPath;
else
qDebug() << "Not compiled for Windows";
Should work.
I think another very reasonable way to get the Windows directory would be to get it from the environment passed to the program:
QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
qDebug() << env.value("windir");
https://doc.qt.io/qt-5/qprocessenvironment.html
I don't think there is a specific Qt function to do this.
The nearest is QSysinfo which tells you the windows version. However SHGetFolderPath() shoudl work in Qt just as well as any other win API call.
ps In Windows vista-> this is replaced with SHGetKnownFolderPath
Here is a one line solution:
QString winPath = QString::fromUtf8(qgetenv("windir"));
This can also be used for any environment variable. I am not sure if qgetenv is available in Qt4 but it is in Qt5.
If your application is not Terminal Services aware, you may get a different directory under TS environment. Found this out myself today, not that I've ever been bit by %windir% or %SystemRoot% or using the ShGetKnownFolderPath or GetWindowsDirectory APIs.
I've opted for using GetSystemWindowsDirectory which exists Windows 2000 and upward. Microsoft's page for the function is here.
Further explanation by Raymond Chen is here.
Finally, the code...
It's written in Delphi 6. Sorry about that :) It's what I'm coding in at the moment, but if you have code for GetWindowsDirectory in your language, then just a few copy + renames are needed as the function signatures are identical. Note: this code is ANSI (...single byte chars in Delphi 6).
function GetSystemWindowsDirectoryA(lpBuffer: PAnsiChar; uSize: UINT): UINT; stdcall; external kernel32 name 'GetSystemWindowsDirectoryA';
function GetSystemWindowsDirectory: string;
var
buf: array[0..MAX_PATH] of Char;
resultLength: Cardinal;
begin
resultLength := GetSystemWindowsDirectoryA(#buf, SizeOf(buf));
if resultLength = 0 then
RaiseLastOSError;
SetLength(Result, resultLength);
Move(buf, PChar(Result)^, resultLength);
end;

how to use C++ load a COM server written in C#?

I am trying to use a COM server generated by Visual Studio 2010 .
When I run CreateInstance(..) , I get error code 0x80040154 .
I enabled fusion log and ran fuslogvw . Fuslogvw reported that loading of assembly (by unknown caller assembly)
mscorlib.resources, Version=4.0.0.0, Culture=zh-HK, PublicKeyToken=b77a5c561934e089
I have already installed .net framework 4 language pack for traditional chinese and also simplified chinese .
Please help . Thanks in advance.
My c++ code is as follow:
#include "stdafx.h"
#import "/Project/TestCOM/MyProject.tlb"
#include <comutil.h>
int _tmain(int argc, _TCHAR* argv[])
{
CoInitialize(NULL);
MyProject::_PHPStarterPtr pCalc;
HRESULT hRes = pCalc.CreateInstance(__uuidof(MyProject::PHPStarter));
if(FAILED(hRes))
{
printf("MyProject::_PHPStarterPtr failed w/err 0x%08lx\n", hRes); // it printed MyProject::_PHPStarterPtr failed w/err 0x80040154
}
else
{
pCalc->AddRef();
bstr_t s("hello");
bstr_t outStr = pCalc->Echo(s);
printf("outStr = %s\n", (const char *)outStr);
pCalc->Release();
printf("Dispose() done\n");
}
CoUninitialize();
return 0;
}
0x80040154 means "class not registered". To register COM components inside .NET assemblies, you use regasm.exe tool from the .NET framework directory. It can be done manually, or as a custom post-build step.

Get path to My Documents

From Visual C++, how do I get the path to the current user's My Documents folder?
Edit:
I have this:
TCHAR my_documents[MAX_PATH];
HRESULT result = SHGetFolderPath(NULL, CSIDL_MYDOCUMENTS, NULL, SHGFP_TYPE_CURRENT, my_documents);
However, result is coming back with a value of E_INVALIDARG. Any thoughts as to why this might be?
It depends on how old of a system you need compatibility with. For old systems, there's SHGetSpecialFolderPath. For somewhat newer systems, there's SHGetFolderPath. Starting with Vista, there's SHGetKnownFolderPath.
Here's some demo code that works, at least on my machine:
#include <windows.h>
#include <iostream>
#include <shlobj.h>
#pragma comment(lib, "shell32.lib")
int main() {
CHAR my_documents[MAX_PATH];
HRESULT result = SHGetFolderPath(NULL, CSIDL_PERSONAL, NULL, SHGFP_TYPE_CURRENT, my_documents);
if (result != S_OK)
std::cout << "Error: " << result << "\n";
else
std::cout << "Path: " << my_documents << "\n";
return 0;
}
Use the SHGetFolderPath Windows API function and request CSIDL_MYDOCUMENTS.
Using Visual Studio 2017 with an MFC application under Windows 10 I am using the following code snippet with SHGetKnownFolderPath function to get the current user's Documents folder:
#include <string> // include file for C++ native strings
// . . . other code.
PWSTR ppszPath; // variable to receive the path memory block pointer.
HRESULT hr = SHGetKnownFolderPath(FOLDERID_Documents, 0, NULL, &ppszPath);
std::wstring myPath;
if (SUCCEEDED(hr)) {
myPath = ppszPath; // make a local copy of the path
}
CoTaskMemFree(ppszPath); // free up the path memory block
Note that the documentation has this to say about the path variable usage and the path returned:
ppszPath [out]
Type: PWSTR*
When this method returns, contains the address of a pointer to a
null-terminated Unicode string that specifies the path of the known
folder. The calling process is responsible for freeing this resource
once it is no longer needed by calling CoTaskMemFree. The returned
path does not include a trailing backslash. For example, "C:\Users" is
returned rather than "C:\Users\".
For a list of the FOLDERID_ arguments possible see the MSDN article KNOWN_FOLDER_FLAG enumeration.
Note that CSIDL_PERSONAL will not return the desired folder if the user has changed the default save folder in the Win7 Documents library. To get the right folder, you need to use SHLoadLibraryFromKnownFolder to obtain the IShellLibrary for the Documents library, use IShellLibrary::GetDefaultSaveFolder to get the IShellItem for the library's default save folder, and finally use IShellItem::GetDisplayName to get the folder name.
std::string GetMyDocumentsFolderPath()
{
wchar_t Folder[1024];
HRESULT hr = SHGetFolderPathW(0, CSIDL_MYDOCUMENTS, 0, 0, Folder);
if (SUCCEEDED(hr))
{
char str[1024];
wcstombs(str, Folder, 1023);
return str;
}
else return "";
}
cout<<GetMyDocumentsFolderPath()<<endl;
how about this solution? Its working fine for me.