How to: Convert System::String to Standard String

 

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The latest version of this topic can be found at How to: Convert System::String to Standard String.

You can convert a String to std::string or std::wstring, without using PtrToStringChars in Vcclr.h.

// convert_system_string.cpp  
// compile with: /clr  
#include <string>  
#include <iostream>  
using namespace std;  
using namespace System;  
  
void MarshalString ( String ^ s, string& os ) {  
   using namespace Runtime::InteropServices;  
   const char* chars =   
      (const char*)(Marshal::StringToHGlobalAnsi(s)).ToPointer();  
   os = chars;  
   Marshal::FreeHGlobal(IntPtr((void*)chars));  
}  
  
void MarshalString ( String ^ s, wstring& os ) {  
   using namespace Runtime::InteropServices;  
   const wchar_t* chars =   
      (const wchar_t*)(Marshal::StringToHGlobalUni(s)).ToPointer();  
   os = chars;  
   Marshal::FreeHGlobal(IntPtr((void*)chars));  
}  
  
int main() {  
   string a = "test";  
   wstring b = L"test2";  
   String ^ c = gcnew String("abcd");  
  
   cout << a << endl;  
   MarshalString(c, a);  
   c = "efgh";  
   MarshalString(c, b);  
   cout << a << endl;  
   wcout << b << endl;  
}  

test  
abcd  
efgh  

Using C++ Interop (Implicit PInvoke)

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