System::String -> std::string

re: System::String -> std::string

David Larsson — Thu, 03 Jun 2004 17:27:00 GMT

Are there any plans to, ahem, extend std::string to include constructors and extraction methods for String^, like ATL::CString currently has?
As a sidenote, this is not the first time I find myself wanting one or two features from CString in std::string, to make the decision for which of the two classes to use for a native Windows C++ application a bit easier...
Either way, I'm really looking forward to the new C++/CLI. Actually, the /clr switch works amazingly well even today.

re: System::String -> std::string

Anson Tsao [MSFT] — Fri, 04 Jun 2004 22:01:00 GMT

In Whidbey we'll be supplying much more direct approach to do this type of marshalling via a library.

void F( String^ s )
{
string s1 = marshal_to<string>( s );
String^ s2 = marshal_to<String^>( s1 );
}

If you already have a char*, and want to get a System::String from it, all you have to do is this:

void F( const char* s )
{
String^ s1 = gcnew String( s );
}

re: System::String -> std::string

stan lippman — Thu, 17 Jun 2004 16:26:00 GMT

as david larsson's ahem indicates, extending the standard ISO-C++ string independent of a standard's body is, i think, unlikely at this point. however, as anson's mail indicates, there is lots of thought being given on how to help users interoperate between the native and managed platforms, and david's request for support in this is not at all unreasonable.

re: System::String -> std::string

stan lippman — Thu, 17 Jun 2004 19:16:00 GMT

Yves Dolce -- the conscience of the blogs -- rightly pointed out that they two conversion samples needlessly prolong the pinning of the internal System::Char array of the String, and has proposed the following preferred alternatives,

bool To_CharStar( String^ source, char*& target )

{

int len = (( source->Length+1) * 2);

target = new char[ len ];

pin_ptr<const wchar_t> wch = PtrToStringChars( source );

return wcstombs( target, wch, len ) != -1;

}

bool To_string( String^ source, string &target )

{

int len = (( source->Length+1) * 2);

char *ch = new char[ len ];

bool result ;

{

pin_ptr<const wchar_t> wch = PtrToStringChars( source );

result = wcstombs( ch, wch, len ) != -1;

}

target = ch;

delete ch;

return result;

}

re: System::String -> std::string

Jonathan Pryor — Fri, 02 Jul 2004 12:00:00 GMT

In To_string(), shouldn't

delete ch;

actually be

delete[] ch;

Since you're allocating an array, you really should use the array deletion expression...

re: System::String -> std::string

stan lippman — Wed, 07 Jul 2004 18:39:00 GMT

you are correct. it is a bad habit for an old dog who was programming with the language before this was added, and of course in current implementations, its absence is actually both non-fatal and possibly more efficient.

Managed C++ - Page 3 | keyongtech

Managed C++ - Page 3 | keyongtech — Thu, 22 Jan 2009 04:06:37 GMT

PingBack from http://www.keyongtech.com/2327213-managed-c/3

I am a fresh Visual C++ .NET Developer. Convert char[1024] to System::String | keyongtech

Thu, 22 Jan 2009 12:17:07 GMT

PingBack from http://www.keyongtech.com/737353-i-am-a-fresh-visual