Read a file XML with mfc C++

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C++

MFC

I searched on internet and I found that to read a file xml I must use namespace System and namespace System::Xml..my code:

<pre> if (PathFileExists(t))
    {
        XmlTextReader^ reader = gcnew XmlTextReader("C:\\Elitron\\Mail\\mail_data.xml");

        while (reader->Read())
        {
            switch (reader->NodeType)
            {
            case XmlNodeType::Element: // The node is an element.
                Console::Write("<{0}", reader->Name);

                while (reader->MoveToNextAttribute()) // Read the attributes.
                    Console::Write(" {0}='{1}'", reader->Name, reader->Value);
                Console::WriteLine(">");
                break;
            case XmlNodeType::Text: //Display the text in each element.
                Console::WriteLine(reader->Value);
                break;
            case XmlNodeType::EndElement: //Display the end of the element.
                Console::Write("</{0}", reader->Name);
                Console::WriteLine(">");
                break;
            }
        }
    }

What I have tried:

but when I compile I have this error:

it isn't possible to use nullptr..I don't know why I have this error