I want to save the contents of a ComboBox to a file. The code below correctly shows a MessageBox with "Marker 4" (the text in the ComboBox), but the saved file contains "03038D8C" instead of "Marker 4", I guess this is the memory address of the variable or something similar? How can I correctly output the "Marker 4"-string to the file?
private: System::Windows::Forms::ComboBox^ cmbMarker;
private: System::String^ strMarkerText;
...
strMarkerText = this->cmbMarker->Text;
...
ofstream myfile;
WIN32_FIND_DATA data;
pin_ptr<const wchar_t> wname = PtrToStringChars(strMarkerText);
FindFirstFile(wname, &data);
::MessageBox(0, wname, L"Marker inserted", MB_OK);
myfile <<"=====MARKER '" << wname <开发者_如何学Python< "' INSERTED AT " << datetime << " =====" << endl;
[There may be more than this wrong with this snippet, I'm not from a C++/CLI background but appreciate your help! There are no compiler errors and the code runs fine except for the issue described above, i.e. that not the cleartext-string-contents are written to the file ("Marker 4"), but "03038D8C".]
Thanks,
NickThe problem is that you're using a narrow stream with a wide string. Use std::wofstream
instead of std::ofstream
and it should work fine.
That being said, I agree with @jonsca -- why drag iostreams into a C++/CLI app?
I'm not sure of your application's requirements, but have you considered using the .NET "equivalents" of the functions, like System::IO::Directory
methods (specifically GetFiles
in place of FindFirstFile
), and the System::IO::StreamWriter
in place of the ofstream
object? This way the code in this section jives with the CLR portion of your code.
I know that's not precisely what you were asking for, but I have a feeling that the pointer in your code might need to be handled differently, and I'm unsure if would have to be marshaled across the managed/unmanaged barrier.
I ended up converting the System::String^
to a std:str
and directly inserted this (rather than converting it to a wchar_t
).
The mix between native c++ and CLI is because I'm building on a SDK-example built in native c++, but wanted to add a form to it (in Visual Studio 2008), which turned it into this "mix". I realize that that's not optimal, but so far, it seems to work :-)! I'll try to only use CLI-equivalents if I run into any more errors going forward. Thanks for your help!
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