Convert a string from c to managed string.

using namespace System::Runtime::InteropServices;

// This function converts UniChar to C# String by using Marshalling
System::String^ ToManagedString(UniChar* bufferP, int32 length)
{
IntPtr ptr = (IntPtr)bufferP;
String^ managedString = Marshal::PtrToStringUni(ptr, length);

return managedString;
}