'System::String ^' to 'LPCWSTR'

Question

I want to convert System::String ^ to LPCWSTR.

for

FindFirstFile(LPCWSTR,WIN32_FIND_DATA); 

Please help.

Answer 1

To convert a System::String ot LPCWSTR in C++/CLI you can you use the Marshal::StringToHGlobalAnsi function to convert managed strings to unmanaged strings.

System::String ^str = "Hello World";

IntPtr ptr = System::Runtime::InteropServices::Marshal::StringToHGlobalAnsi(str);

HANDLE hFind = FindFirstFile((LPCSTR)ptr.ToPointer(), data);

System::Runtime::InteropServices::Marshal::FreeHGlobal(ptr);

Answer 2

The easiest way to do this in C++/CLI is to use pin_ptr:

#include <vcclr.h>

void CallFindFirstFile(System::String^ s)
{
    WIN32_FIND_DATA data;
    pin_ptr<const wchar_t> wname = PtrToStringChars(s);
    FindFirstFile(wname, &data);
}