cannot convert from 'System::String' to 'LPCSTR'

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- Previous
  - 1
    - what's the different between #incldue " xxx" and #include <xxx > Hi All, When we include a header file, we will use #include "xxx " or #include "xxx" What's the difference? Best regards, Boki. Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247943
  - 2
    - System Class initialization complete? Hi, I have a class that has an initialization thread spun up by a static member. I don't want this thread to run until *all* the classes are done initializing. How can I tell when all the classes (mine and MFC's) are done initializing and it's safe to start creating instances of my classes? Thanks... Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247936
  - 3
    - Displaying Grayscale Images How do I display Grayscale Images from a file using VC? Thanks Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247934
  - 4
    - Cannot instantiate abstract class Why do I get C2259: 'Derived': cannot instantiate abstract class from the following scenario? class Abstract { public: virtual int GetType() = 0; virtual int GetApp() = 0; virtual void GetVersion() = 0; ... } class Derived : public Abstract { public: int GetType(); int GetApp(); void GetVersion(LPTSTR versio, size_t versionSize); ... } In class 'Derived' I've written an implementation for all three pure virtual methods. Still the compiler claims the class 'Derived' is abstract if I try to instantiate it??? Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247929
  - 5
    - My first C++ Application in VC++ 2005 Express! Dear All, My name is Davin Eastley and I'm 13 years old. I wrote my first C++ 2005 Application yesterday with no resources by playing around with C++ Express Edition for half the day. I assigned x as an int (with the value of 20) and got the compiler to tell me whether it was greater than 2 or not. This was the code I used: private: System::Void button1_Click(System::Object^ sender, System::EventArgs^ e) { int x; x = 1; //this assigns x as an int //(a variable - data type -) if (x >= 2) { // if x is greater than 2, output a messagebox saying x is greater than 2. MessageBox::Show(L"x is greater than 2!"); } if (x < 2) { // if x is lower than 2, output a messagebox saying x is lower than 2. MessageBox::Show(L"x is lower than 2!"); } } This is straight from the compiler. This is the new style of C++ 2005. I am very happy to write my first application in C++. I also wrote a console application which uses Console::WriteLine instead of the messagebox equivalent. I still want to know how to use the cout and cin keywords though. Time to do some more learning on C++! Regards, Davin Eastley -------------- www.davineastley.tk Forums Home Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247926
  - 6
    - Calculate the length of a MIDI file My app opens a midi file using the MCI api. how to retrieve the length of the MIDI in seconds? The MCI_STATUS_LENGTH status command returns a number, but how to convert it to seconds? thanks Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247924
  - 7
    - Question about import directive I want to learn more about how the import directive works. I just used for the first time recently with the vbscript regex com object. I googled the import directive but I couldn't find alot of information on the import directive just its usage in specific cases. I wanted to ask if anyone knew of any books or websites that explain more about import directive. Thanks Danny Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247918
  - 8
    - Stack Overflow Hi All, What cause a Stack Overflow? Is it that the program used more memory than that was alloted for it? I converted my application to Unicode and it statredgiving this problem. It's not getting stuck in an infinite loop, and if I step into it, it's not getting stuck at any particular line which is alotting any memory, it crashes at the beginning of a function. Maybe since I converted all those chars to TCHARs now it's using up double the memory, and running out of memory???? Plese enlighten me Thanks a lot in advance Srishti Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247914
  - 9
    - Cannot delete a memory mapped file at end of program Hi All, wonder if someone can point out what I am doing wrong.....I am creating memory mapped files on win2000 using CreateFile and CreateFileMapping and MapViewOfFile. At the end of the program I figured it would be nice to clean up these files but when I issued the del <filename> as a system command (or if I try the DeleteFile function) I get a message saying that the file is in use by another process.....Is there something else I must do to release a file that I have set up using CreateFile and CreateFileMapping and MapViewOfFile??? Any tips greatly appreciated... ////////////////////////////////////////////////////////////////////////////////////////////// // When the job ends deleted the wait file, the kill file, and any memory mapped files that // // have been created by this process. // ////////////////////////////////////////////////////////////////////////////////////////////// ptr_WaitFile->Delete() ; ptr_KillFile->Delete() ; for (index1 = 0 ; index1 < ws_used_memory_mapped_files ; index1++) BEGIN_ #if defined (_MSC_VER) UnmapViewOfFile(ptr_MemMapBuffer_array[index1]) ; DWORD dw1 = GetLastError(); CloseHandle(ws_HandleForMemMapFile_array[index1]) ; DWORD dw2 = GetLastError(); #endif ptr_DimensionTable_File[index1]->Delete() ; END_ Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247899
  - 10
    - Black drag image I am using WTL and getting a blackbox for my drag Image. Any help greatly welcomed. CImageList *m_pDragImage = new CImageList(); <OnBeginDrag> m_pDragImage->Create(16,16,ILC_COLOR16 ,0,10); CBitmap bm; bm.LoadBitmap(IDB_DRAGIMAGE); m_pDragImage->Add(bm,RGB(0,0,0)); m_pDragImage->BeginDrag(1, CPoint(nOffset, nOffset)); m_pDragImage->DragEnter(m_hWnd, a->ptAction); <OnMouseMove> m_pDragImage->DragShowNolock(TRUE); m_pDragImage->DragMove(pt); Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247892
  - 11
    - Generating makefile dependencies Hi, Many compilers have a command-line option, usually -m or -M, to generate dependencies for inclusion in a makefile. Does any version of the VC++ compiler support such an option? I know it used to be possible to do it through the IDE and that this feature was abolished; I'm just interested in command-line options. Best, Jonathan Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247888
  - 12
    - Best way to handle SEH and COM Exceptions Not sure if this is the right section of the forums to post but here goes. I work as an escalation engineer and we have an application that is using VB and C++ dll. The VB app passes in some XML to the C++ code which calls a database using ADO with the #import statement. The #import looks like this: #import "C:\Program Files\common files\system\ado\msado15.dll" no_namespace rename("EOF","adoEOF") If I understand everything the #import statement generates some .tlh and .tli files that wrap ADO. Also adding error handling by calling _com_raise_error which throws internaly _com_errors. My problem is this. The app is throwing (maybe better to say raising) an exception inside a C++ try block that was being eaten by the catch(...). Not good because we are losing the exception. So I removed the catch(...) and added a SetUnhandledExceptionFilter( HandleCrash ) in the DLLMain. When the HandleCrash exception filter is call I call MiniDumpWriteDump which seems to be working fine. Is this good programming practice and will it produce the most reliable code? When the HandleCrash is call I believe the only thing I can really do is write a minidump and end the program. Is this write? And now the code :) Thank you in advance for your help! // in dllmain SetUnhandledExceptionFilter( HandleCrash ); // LONG WINAPI HandleCrash( LPEXCEPTION_POINTERS pExs ) { // format file name app and date time of dump FormatFileName( _T("app"), _T(""), file ); // message box to tell user they crashed and dump file has been writen ::MessageBox(... // dump minidump HANDLE hFile = CreateFile( file, GENERIC_READ | GENERIC_WRITE, ... if( ( hFile != NULL ) && ( hFile != INVALID_HANDLE_VALUE ) ) { MINIDUMP_EXCEPTION_INFORMATION mdei; mdei.ThreadId = GetCurrentThreadId(); mdei.ExceptionPointers = pExs; mdei.ClientPointers = FALSE; MINIDUMP_TYPE mdt = MiniDumpNormal; BOOL rv = MiniDumpWriteDump( GetCurrentProcess(), GetCurrentProcessId(), hFile, mdt, (pExs != 0) ? &mdei : 0, 0, 0 ); if( !rv ) _tprintf( _T("MiniDumpWriteDump failed. Error: %u \n"), GetLastError() ); else _tprintf( _T("Minidump created.\n") ); // Close the file CloseHandle( hFile ); } else { _tprintf( _T("CreateFile failed. Error: %u \n"), GetLastError() ); } return EXCEPTION_EXECUTE_HANDLER; } try { // setup connection... hr = pConnection.CreateInstance( __uuidof(Connection) ); // ... code and error checking removed for breviety ... // setup command and parameters ... hr = pCommand.CreateInstance( __uuidof(Command) ); // ... // exception occuring here hr = pCommand->Execute( NULL, NULL, adExecuteStream ); // ... } catch( _com_error &e ) { // log error in log file and continue... } catch( std::exception& e ) { // log error in log file and continue... } // this was originally in the code // but was removed because the exception was being lost catch( ... ) { //do nothing :( } Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247876
  - 13
    - C v6.0 Compiler Needed I have been asked to modify a Microsoft C v6.0 program written in 1991. However, I do not have a Microsoft C compiler. Does anyone know where a C compiler can be obtained? Will any of the MS Visual Products work? Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247870
  - 14
    - WriteFile reports x bytes written, but file does not grow Folks, I'm not quite sure if this is the correct newsgroup to post it, but I'm sure there are experts here that might have an answer to my question. I have developed a .net isapi DLL (Web Service) that uses a COM object to cut and merge WAV files. Now, the Web Service and the COM object work fine on my XP machine, writing the file as it should. However, when I run the complete system on a Win2000 machine, my writefile in the COM object acts strangely. It should write some buffer to a file, and the BytesWritten returns exactly the number of bytes that need to be written, but my file does not grow. I'm offering a total amount of 20 MB to write (in 4096 kB buffers) but the file stays 1 kB. This 1 kB is from a previous WriteFile action that writes a WAV header to the file. So, after writing the wave header, every call to writefile does not result in file growth. Does anyone have similar experience or has seen this kind of behavior before? I appreciate any response. Thanks in advance! Rob Vermeulen. Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247869
  - 15
    - how to convert "ff" (string) to integer 255 for (jjj = 0; jjj < argc-2; jjj++) { itemsg[jjj] = atoi (argv[jjj+2]); } static int jjj; int itemsg[200]; itemsg[jjj] always becomes not... Pls help... Jack Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247865
  - 16
    - Sharing violationin fopen function with "w" flag Hi, I have a a application developed in Visual C++ 6.0. It is running very well in Windows 2000 platform but in XP I have got some random problems. I have been testing and I have seen, I think, that the problem is in fopen function. I am running VMWare machine with XP Pro Service Pack 2. The VMWare is running on Windows 2000. The files are in Windows 2000 and I read the filed trought the net. If I run the same application in Windows 2000 there is not problem. It run OK. The problem is follow: When I call the fopen function in a exact pont, sometimes the system going to down and slowly and when the system return the file hanlde, sometimes return OK and sometimes return 0x00000. I have use the "filemon" tool and, in this situation, the filemon shows: "Sharing violation error" Also, I have compared the systems calls with filemon in W2k and XP and I hav seen that the fopen funtion, in W2k, make a "Query" call but in XP not. I have spent very time in order to discover the problem but I have not seen the solution. Also I have installed several hotfixes after the SP2. Thanks. Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247864
  - 17
    - StreamOut doesn't preserve CFM_LINK settings Hi Everybody, In my rich edit application, I just discovered CFM_LINK and am enjoying having clickable links in my CRichEditCtrl. However, when I use streamOut and streamIn to save my control contents to disk and back, all the RTF formatting is preserved except for the links. Please guide me how to save the RTF document along with the hyperlink. Regards, Prakash. Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247863
  - 18
    - Why this error "error C2146: syntax error : missing ';' before identifier 'Length'" I have a VC++.net Win32 console application, however when I compile , I get this error error C2146: syntax error : missing ';' before identifier 'Length' Explain... Location pointed is typedef struct _LIST { LPLINK Tail; //... List Tail pointer. LPLINK Head; //... List Head pointer. DWORD Length; //... List Length. } LIST; typedef LIST *LPLIST; in List.h Thanks, a.a.cpp Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247860
  - 19
    - outportb available?!?!? Hi there, I would like to create a .dll from legacy code. It includes the inportb and outportb commands. Are inportb and outportb available in any version that can create a dll?? Thanks very much, Russ Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247855
  - 20
    - From Borland C++ 502 to Visual C++ HI,I need help!!! I've the source code of a software written with Borland C++ 5.02 IDE. I want to port this code from Borland C++ 502 to Visual C++ 6. Is this possible?? Do you have any advice for me?? Thank's for All Jasp Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247850
  - 21
    - Moving from C++ to VC++ Hi all. Are there any good web tutorials that teach how to make this move? I don't necessarily need to know MFC inside and out, as MSDN is sufficient for that. Code conventions, MS typedef's that should be used (DWORD for example), and other things that accomplish the same thing in C++ but in VC++ style. I'm a good C++ coder, but my VC++ apps seem to be lacking when I peruse the code presented in this NG. Any help is very much appreciated. Thanks, Mike Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247849
  - 22
    - Control X10 devices + a/v equipment with Bluetooth mobile phone Pluto is a free, open source smart home solution that seamlessl integrates: 1) media with a server for music, movies and tv shows, plu a PVR and DVD Player, 2) a home automation system with touch-scree tablet and Bluetooth mobile phone controllers, 3) a phone system wit video conferencing, 4) a security system that feeds you live video o your mobile phone when there are interruptions, and lets you speak t visitors through your stereos, and 5) a home PC solution. Check it ou at [url]www.plutohome.com[/url] It lets you control your X10 devices with the PC, webpads, pdas an mobile phones, using both scenario shortcuts and interactiv floorplans - laura ----------------------------------------------------------------------- Posted via http://www.codecomments.co ----------------------------------------------------------------------- Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247848
  - 23
    - Member template internal compiler error I am getting an Internal Compiler Error in VC++ 6 with the following code. I'm fairly sure it is well-formed (g++ 3.4.2 compiles it fine). Is there a workaround available? #include <iostream> #include <ostream> class Foo { public: template <int N> static void Test() { std::cout << N << std::endl; } }; int main() { Foo::Test<5>(); /* I.C.E. here */ } Thanks for any help you can provide. Kristo Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247846
  - 24
    - cin.read() failure Hello All, I'm having some trouble with cin and ifstreams while reading some binary data. Everytime I read in character #10 (Line feed,) the stream fails, and I am unable to read any further from the stream, even if I use cin.clear() or cin.peek(). What can do to be able to read past a Line Feed? -Joel Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247843
  - 25
    - Capturing the save click events in Microsoft word. I want to develop an application using MSAA in which I want to trace when a user presses some menu items - like save, print, save as etc. What are the events related to that. For menu open EVENT_SYSTEM_MENUSTART types of event are available but what are the events related to pressing the save , print , save. Regards, Sunil Virmani Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247841
- Next
  - 1
    - allocator question Hi to all, when passing an allocator to SEVERAL containers at the same time, can we rely on the "rebind" mechanism assuming that each container is able to select its own allocator? for example: is the following ok? template <class T, class allocator_t> class MyContainer { std::vector<T, allocator_t> v_; std::map<T, int, std::less<T>, allocator_t> m_; }; or should we be verbose and deduce the correct allocators out of the sub-containers: template <class T, class allocator_t> class MyContainer { typedef typename allocator_t::template rebind<T>::other rebind1_t; std::vector<double, rebind1_t> v_; typedef typename allocator_t::template rebind< std::pair<const T, int>::other rebind2_t; // etc... }; of course version #1 and version #2 declare a class whose members have different types (say, m_ is map<T,int, ... allocator<T> > and map<T,int, ... allocator< std::pair<...> > >), but apart from that, are they "functionally" equivalent? Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247840
  - 2
    - Files in current directory Which API(s) or C/C++ library functions can retrieve all the names of the files in a directory? Thanks Jack Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247828
  - 3
    - Console App - howto determine if an app is a console app How can I find out if an application is a console app or a windows app. I realize that if there the header starts with 0xd4 0x5a it cannot be run in "DOS" mode but that not mean a windows 2000 console app. I have win2k console apps and they also start with 0x4d 0x5a. thanks for the help john Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247827
  - 4
    - parsing command line args in CDialog app Hi, I have a CDIalog MFC based win ap under MSVC 6.0 Now I need to configure it for parsing command line parameters ,,,, where and which function does accept argc, char** argv as there is no main() Kindly help Thanks, a.a.cpp Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247817
  - 5
    - question about retrieving a volume name... i am trying to determine the volume name for each partition on a physical disk resource in a mscs environment. i have already established the ability to enumerate all of the storage resources and get a CLUSPROP_PARTITION_INFO structure for each. when i retrieve the szdevicename property of the structure i get a drive letter for all volumes mounted to a drive letter. i can uset findvolumenameformounpoint by simply appending a \ to the string to get the volume name. however volumes that are mounted to a folder or not at all return a string similar to Disk1Partition4 for their szdevicename. are there any functions or proceedures i can use to retrieve the volume name only knowing the above mentioned string? my searching has turned up nothing. thanks for your help!!! Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247809
  - 6
    - unresolved external symbol __abs64 Is _abs64 not available in the DLL libraries? I am using Visual Studio 2003. A program that uses the _abs64 function links fine with the multithread debug (/MTd), but not multithread debug dll (/MDd). Is this a bug or by design? Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247808
  - 7
    - should i do SysFreeString here? i'm just doing some wrap class for msxml and got some problem? i'm using the raw interface in msxml.h, not smart pointer. (visual studio 2003) sample code like this: //--start------------------------------------------- { IXMLDOMDocument* pDoc = NULL; HRESULT hr = ::CoCreateInstance(CLSID_DOMDocument, NULL, CLSCTX_INPROC_SERVER, IID_IXMLDOMDocument, (void**) &pDoc); hr = pDoc->put_async(VARIANT_FALSE); hr = pDoc->put_validateOnParse(VARIANT_FALSE); hr = pDoc->put_resolveExternals(VARIANT_FALSE); CComVariant varFile(_T("c:\\aa.xml")); VARIANT_BOOL status; hr = pDoc->load(varFile, &status); BSTR bstrXML = NULL; pDoc->get_xml(&bstrXML); //*********************** // doing some processing for bstrXML; // ... // SysFreeString(bstrXML); //should i do SysFreeString here? //*********************** pDoc->Release(); } //--end--------------------------------------------- i have used _CrtDumpMemoryLeaks() and _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ) to detect memory leak. but whether i do SysFreeString or not, there is no memory leak detected. i believe use SysFreeString() here is a good behave. and i have viewed some code from others. someone use, someone not. i am very confused that is it necessary to do SysFreeString here? and anyone can help me? thanks! Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247807
  - 8
    - Scrollbar controls in Win32 -- Please help Bear with me, I'm a complete newbie to Win32 programming. I want a scrollbar in the upper corner of my app, but it's not showing up. Here is my code: #include "stdafx.h" #include <commctrl.h> #include "resource.h" LRESULT __stdcall wcexProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) { switch(msg) { case WM_CREATE: { HWND hScroll; if(!(hScroll = CreateWindowEx(0L,"SCROLLBAR",NULL,WS_VISIBLE|WS_CHILD,0,0,200,CW_USEDEFAULT,hwnd,NULL,GetModuleHandle(NULL),NULL))) MessageBox(NULL,"Scrollbar could not be created","error",0); } break; default: return DefWindowProc(hwnd,msg,wParam,lParam); } return 0; } int __stdcall _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { InitCommonControls(); HWND hwnd; WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = 0; wcex.lpfnWndProc = wcexProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(NULL,(LPCSTR)IDI_RACER); wcex.hCursor = LoadCursor(NULL,IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1); wcex.lpszMenuName = NULL; wcex.lpszClassName = "wcex"; wcex.hIconSm = LoadIcon(NULL,(LPCSTR)IDI_SMALL); if(!RegisterClassEx(&wcex)) { MessageBox(NULL,"Couldn't register wcex","error",0); } if(!(hwnd = CreateWindowEx(0,"wcex","Main Window",WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,hInstance,NULL))) { MessageBox(NULL,"Could not create main window","error",0); } ShowWindow(hwnd,nCmdShow); UpdateWindow(hwnd); MSG msg; while(GetMessage(&msg,NULL,0,0) > 0) { TranslateMessage(&msg); DispatchMessage(&msg); } return msg.wParam; } Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247791
  - 9
    - Theoretical Question A colleague posed an interesting question to me today. In C or C++, why can't I write this: void MyFunction() { unsigned var : 14; // ... } The compiler already knows how to do the shifting and masking for bit fields in structures. The above is nothing more than syntactic sugar for, say: void MyFunction2() { struct { unsigned f : 14; } var; // ... } But I could think of no good reason why the first one couldn't also be done, and there are certain problem domains where that kind of thing could prove useful. -- - Tim Roberts, timr@probo.com Providenza & Boekelheide, Inc Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247789
  - 10
    - COM question This might be considered an elementary question for those with COM emblazened upon their belt buckles, but I know just enough about it to be dangerous! Here goes... If I include <dskquota.h>, I can use the following code just fine: IDiskQuotaControl *lpDiskQuotaControl; IEnumDiskQuotaUsers *lpEnumDiskQuotaUsers; HRESULT hr = CoCreateInstance(CLSID_DiskQuotaControl, NULL, CLSCTX_INPROC_SERVER, IID_IDiskQuotaControl, (LPVOID*)&lpDiskQuotaControl); if (SUCCEEDED(hr)) { hr = lpDiskQuotaControl->Initialize(_bstr_t("c:\\"), TRUE); if (SUCCEEDED(hr)) { hr = lpDiskQuotaControl->CreateEnumUsers(NULL, 0, DISKQUOTA_USERNAME_RESOLVE_SYNC, &lpEnumDiskQuotaUsers); ... } lpDiskQuotaControl->Release(); } If, however, I wanted to use smart pointers instead with #import <dskquota.dll> then the CreateEnumUsers() method does not show up in the .tlh or .tli file. There also does not appear to be an interface for the users (plural). Is it supposed to be this way, or what am I doing wrong? Thanks, DC Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247788
  - 11
    - How to get selected files Filename and full path? Hi, i am working on a kind of protection application that must react when a user selects (only hover resp. mark, not execute!) a file that in turn will be market as selected. I need to find out the files full path and name. How can i do this. Is there a WM_ Message or equal available for this? Systemwide Windows Hook? How can this be accomplished.....? :-) Thanks in advance... Kerem Gümrükcü Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247765
  - 12
    - ::exception Hi, Someone can explain to me the diference between CODE_A and CODE_B? //double calc( int a, int b ) ; //double calc( int a, int b ) throw(MathError); why "throw(MathError);" CODE_A -------------------------------------------------------------- class MathError { private: string message; public: MathError( const string& s) : message(s) {} const string& getMessage() const {return message;} }; double calc( int a, int b ) throw(MathError); int _tmain(int argc, _TCHAR* argv[]) { int x, y; bool flag = false; do { try // try block { cout << "Enter two positive integers: "; cin >> x >> y; cout << x <<"/"<< y <<" = "<< calc( x, y) << '\n'; flag = true; // To leave the loop. } catch( MathError& err) // catch block { cerr << err.getMessage() << endl; } catch( ...) { cerr << "3333" << endl; } }while( !flag); // continued ... return 0; } double calc( int a, int b ) throw (MathError) { if ( b < 0 ) throw MathError("Denominator is negative!"); if( b == 0 ) throw MathError("Division by 0!"); return ((double)a/b); } CODE_B -------------------------------------------------------------- class MathError { private: string message; public: MathError( const string& s) : message(s) {} const string& getMessage() const {return message;} }; double calc( int a, int b ) int _tmain(int argc, _TCHAR* argv[]) { int x, y; bool flag = false; do { try // try block { cout << "Enter two positive integers: "; cin >> x >> y; cout << x <<"/"<< y <<" = "<< calc( x, y) << '\n'; flag = true; // To leave the loop. } catch( MathError& err) // catch block { cerr << err.getMessage() << endl; } catch( ...) { cerr << "3333" << endl; } }while( !flag); // continued ... return 0; } double calc( int a, int b ) { if ( b < 0 ) throw MathError("Denominator is negative!"); if( b == 0 ) throw MathError("Division by 0!"); return ((double)a/b); } Thanks Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247760
  - 13
    - sending message from UI thread to the main thread I have a main control in which I have a loop which processes video frames. To be able to see the results in real time, I created a dialog in another thread which displays the data as they become available (the main thread populates a global array, and the second thread picks the last element and displays it.) I need to access some functions (e.g. change settings of video aquisition) in the main thread from within the second thread while the loop in the main thread is running. I know I have to use messages to do that, but SendMessage needs a pointer to the main window, and I can't pass a CWnd * to the secondary thread. So, how do I call a main thread function from a secondary thread? Here's a sketch of what I have now: //in main control: pThread = (CUIThread*)AfxBeginThread(RUNTIME_CLASS(CUIThread)); pThread->m_pMainWnd = FromHandle(this->m_hWnd);//this does not work //in UIThread class: CUIThread::InitInstance() { CWnd * cwnd = m_pMainWnd; m_plot = new Plot_dialog(cwnd); return TRUE; } //in Plot_dialog: Plot_dialog::Plot_dialog(CWnd* pParent) {} Plot_dialog::UpdateSetting() { pParent->SendMessage(WM_PLOT_TO_MAIN, 0, (LPARAM) &CCM); } Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247759
  - 14
    - How to modify CString in the debugger for VC6.0? How can a CString variable be modified in the debugger with VC 6.0? For instance I want to change "xxx" to "" so that I can test a certain code path. Thanks. Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247754
  - 15
    - memory allocation problems Hello, this is probably most fundamental but I don't code in C++ often and I'm just not getting why the code is crashing with a: Unhandled exception at 0x77f75a58 in FileIOTest.exe: User breakpoint I have a function that calls this line of code: char* buffer = new char[sizeof(char) * (strlen(curtime) + strlen(msg) + 3)]; The first time I call the function, all is well but subsequent times it crashes with the above exception. All I'm doing is a strcpy, strcat and writing to a file in the funciton and then I delete buffer memory using delete. What could the problem be. Sorry is this is just really stupid... Steve Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247739
  - 16
    - Converting a 4 byte char to a double Hi there, I'm trying to convert the 4 bytes returned by a time server to a double value, I know this should be pretty straight forward but I think I have gone wrong somewhere along the lines. At the moment I am doing the following string pStrBuffer; <pStrBuffer is now assigned the value> double pDblSeconds; int pIntChar; for(pIntChar=0;pIntChar<pStrBuffer.length()-1;pIntChar++) { double pDblCurValue = 0; pDblCurValue = (int)pStrBuffer.c_str()[pIntChar]; pDblCurValue = ((int)pDblCurValue << (8*pIntChar)); pDblSeconds += pDblCurValue; } Unfortunately I am recieving 0 as my value at the moment. Any ideas on what I'm doing wrong? Thanks laods in advance! -- Nick Pateman --------------------------------------------------------------- Any views expressed above are my own Without predjudice Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247737
  - 17
    - OT: How to search binary occurences in files Hi, In case I have a set of files to search in for a binary pattern (For example FF A1 23 0a), is there any free software which can do this job? I don't want to open a hell lots of files to search for the stream individually... cos it takes ages to do so.... I have already about > 100 files to search in..... sorry for OT question.... Thanks Jack Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247736
  - 18
    - Passing GET variables to a CGI script from C Hi, I'm trying to pass variables to a local web page (with JavaScript) from C. I've tried to do this with ShellExecute and WinExec as follows: ShellExecute(m_hWnd, "open", "file:///c:/some_page.html?var1=some_val&var2=some_other_val", "", NULL, SW_SHOWNORMAL); ... which opens up the browser and webpage correctly, but the query string gets lost along the way. I've also tried setting the QUERY_STRING environment variable prior to loading the page, which doesn't work - I'm assuming it gets overwritten when the page loads with no query string appended to the url. Any suggestions? Thanks, -Nick Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247735
  - 19
    - vector and debug mode Hi I am using vector class (via #include<vector>) as a dynamic array. vector <int> list; int array [10]; With the array definition I can se eg. the 7. element in the watch window in the debugger (when execution has stopped due to a breakpoint or an exception) by typing array[7]. This is not possible for the vector definition. Is it possible to somehow circumvent this, so I can see eg. the 7. element of the list in the watch window?? Any ideas would be welcome! Regards, Peter Stausholm Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247730
  - 20
    - GetOpenFileName set to "My Computer" How do I set the default location to "My Computer" when using the GetOpenFileName call? I have tried the following but CSIDL_DRIVES doesn't appear to work. Any ideas? WCHAR szFile[260] = _T("text.txt"); WCHAR szPath[MAX_PATH] = _T(""); LPITEMIDLIST pidl; HRESULT hr = SHGetSpecialFolderLocation(NULL, CSIDL_DRIVES, &pidl); if(SUCCEEDED(hr)) SHGetPathFromIDList(pidl, szPath); ZeroMemory(&ofn, sizeof(OPENFILENAME)); ofn.lStructSize = sizeof(OPENFILENAME); ofn.hwndOwner = hwnd; ofn.lpstrFile = szFile; ofn.nMaxFile = sizeof(szFile); ofn.lpstrFilter = _T("All\0*.*\0Text\0*.txt\0"); ofn.nFilterIndex = 1; ofn.lpstrFileTitle = NULL; ofn.nMaxFileTitle = 0; ofn.lpstrInitialDir = szPath; ofn.Flags = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST; if(GetOpenFileName(&ofn)==TRUE) // File dialog Open selected {} -- -- mnlarsen Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247729
  - 21
    - Need some help on ActiveX control, interface declarations Hi, I have an ATL composite control, I have declared an inteface method of the control as taking a BOOL datatype. When I insert this component into the client program. The code that is generated has the method taking a long data type. When I call a component method taking about 16 parameters in which some of the parameters are BOOL (they get translated in the client to long as I explained earlier) when I make a call too the component method.the parameters are not being passed correctly to the component. Can the esteemed members please help me out on this. Regards, D.Ramesh Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247725
  - 22
    - warning LNK4221 Hi, Can anyone explain me the warning which says "warning LNK4221: no public symbols found; archive member will be inaccessible". I'm able to build the static lib, but unable to debug the values (when used in the test application by static linking this library). I didn't find info. about this warning in MSDN. Thanks, Aparna Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247723
  - 23
    - CHARFORMAT::dwReserved ? Hi In writing a syntax highlighter, I want to be able to tell whether a certain portion of text in the richedit control is block comments or line comments. However these will both be the same color. Is there any reason why I shouldn't use the dwReserved flag of the CHARFORMAT structure? It says in the documentation 'reserved - must be zero'. But does that actually mean 'reserved - completely ignored' ? Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247715
  - 24
    - Static/ non-static member access // in .h file class CSingleton { public: static CSingleton* Instance(); protected: CSingleton(); CSingleton(const CSingleton&); CSingleton& operator= (const CSingleton&); ~CSingleton(); private: static CSingleton* pinstance; }; // in .cpp file CSingleton* CSingleton::pinstance = 0; CSingleton::CSingleton() { } CSingleton::~CSingleton() { } CSingleton* CSingleton::Instance () { if (pinstance == 0) { pinstance = new CSingleton(); //Line A pinstance->DummyFn(); //Line B //CSingleton sgTon; } return pinstance; } In Line A, in the above implementation of a Singleton class: why is the static method Instance() allowed to create an instance of the class on the heap, and thereby invoke the constructor (which is non-static)? Similarly, in Line B a non-static method 'DummyFn' is allowed to be invoked from the static method. Why is it so? TIA, Sucharit Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247713
  - 25
    - How to make ActiveX component in VC++ 6.0 ? Hi, I have a set of programs...I need to make an Active X component over those functions... Suggestions required... Thanks, a.a.cpp Tag: cannot convert from 'System::String' to 'LPCSTR' Tag: 247711

I am trying to use Managed C++ to get the dir from which my .msi was
launched and set a property with that value. I am pretty lost. I have no
clue if I am even on the right track, but this all seems so simple. Right
now the last line below - I can't get the 3rd arg right. It needs to be an
LPCSTR.

String *cdromDir = NULL;

if ((status = getInstallProperty(hInstall, "OriginalDatabase",
&imageLocation)) != ERROR_SUCCESS) return status;

cdromDir = Path::GetDirectoryName(imageLocation);

USES_CONVERSION;

MsiSetProperty(hInstall, "CDROMDIR", A2W(*cdromDir));

Thanks,

owen

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Re: cannot convert from 'System::String' to 'LPCSTR' by Doug

Doug
Mon Jun 06 23:36:25 CDT 2005

On Mon, 6 Jun 2005 23:25:32 -0500, Owen Corpening wrote:

> I am trying to use Managed C++ to get the dir from which my .msi was
> launched and set a property with that value. I am pretty lost. I have no
> clue if I am even on the right track, but this all seems so simple. Right
> now the last line below - I can't get the 3rd arg right. It needs to be an
> LPCSTR.
>
> String *cdromDir = NULL;
>
> if ((status = getInstallProperty(hInstall, "OriginalDatabase",
> &imageLocation)) != ERROR_SUCCESS) return status;
>
> cdromDir = Path::GetDirectoryName(imageLocation);
>
> USES_CONVERSION;
>
> MsiSetProperty(hInstall, "CDROMDIR", A2W(*cdromDir));

See:

How To Convert from System::String* to Char* in Visual C++ .NET
http://support.microsoft.com/?kbid=311259

--
Doug Harrison
Microsoft MVP - Visual C++

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