转换Platform :: Array <byte> 到String

Question

A have a function in C++ from a library that reads a resource and returns Platform::Array<byte>^

How can I convert this into a Platform::String or an std::string

BasicReaderWriter^ m_basicReaderWriter = ref new BasicReaderWriter()
Platform::Array<byte>^ data = m_basicReaderWriter ("file.txt")

I need a Platform::String from data

Answer 1

If your Platform::Array<byte>^ data contains an ASCII string (as you clarified in a comment to your question), you can convert it to std::string using proper std::string constructor overloads (note that Platform::Array offers STL-like begin() and end() methods):

// Using std::string's range constructor
std::string s( data->begin(), data->end() );

// Using std::string's buffer pointer + length constructor
std::string s( data->begin(), data->Length );

Unlike std::string , Platform::String contains Unicode UTF-16 ( wchar_t ) strings, so you need a conversion from your original byte array containing the ANSI string to Unicode string. You can perform this conversion using ATL conversion helper class CA2W (which wraps calls to Win32 API MultiByteToWideChar() ). Then you can use Platform::String constructor taking a raw UTF-16 character pointer:

Platform::String^ str = ref new String( CA2W( data->begin() ) );

Note: I currently don't have VS2012 available, so I haven't tested this code with the C++/CX compiler. If you get some argument matching errors, you may want to consider reinterpret_cast<const char*> to convert from the byte * pointer returned by data->begin() to a char * pointer (and similar for data->end() ), eg

std::string s( reinterpret_cast<const char*>(data->begin()), data->Length );