从C++中的.NET抽象类派生,System :: IO :: TextWriter

Question

我有一个问题,我正在创建一个派生自抽象类TextWriter的类.

文档 http://msdn.microsoft.com/en-us/library/System.IO.TextWriter(v=vs.110).aspx

来源 http://referencesource.microsoft.com/#mscorlib/system/io/textwriter.cs

因此,所有源代码都在C#中,并且在160-162行上有一个特定的部分,我需要覆盖派生类,使其不被视为抽象(由编译器警告提示):

public abstract Encoding Encoding {
    get;
}

我如何将这一部分翻译成C++来覆盖它？

警告声明'System :: Text :: Encoding ^ System :: IO :: TextWriter :: Encoding :: get(void)'是抽象的(如TextWriter的源代码所示),但是在我尝试的同时覆盖这个"get"函数我得到的错误是我的类包含显式覆盖'get'但不是从包含函数声明的接口派生的.

这是我所拥有的这个函数的C++变体的唯一想法,它告诉我基类中不存在"get"函数:

  System::Text::Encoding^ Encoding::get(void) {
    return nullptr;
  }

显示此问题的最基本示例:

public ref class SampleWriter : public System::IO::TextWriter {
public:

  SampleWriter() {
    // Do Nothing.
  }

  // Need to override 'System::Text::Encoding ^System::IO::TextWriter::Encoding::get(void)'... 
  // Remove this function to see that SampleWriter is inherently abstract and cannot be initialized
  virtual System::Text::Encoding^ Encoding::get(void) override {
    return nullptr;
  }

protected:
  ~SampleWriter() {
    // Do nothing.
  }
};

public ref class SomeForm : public System::Windows::Forms::Form {
public:
  SomeForm(void) {
    InitializeComponent();
    sample_writer = gcnew SampleWriter();
  }

protected:
  ~SomeForm() {
    if (components)
      delete components;
  }

private:
  System::ComponentModel::Container^ components;
  SampleWriter^ sample_writer;

  void InitializeComponent(void) {
    this->components = gcnew System::ComponentModel::Container();
    this->Size = System::Drawing::Size(300, 300);
  }
};

int main() {
  SomeForm^ form = gcnew SomeForm();
  form->ShowDialog();

  return 0;
}

Answer 1

如果使用property定义中的语法SampleWriter怎么办？像这样的东西:

property System::Text::Encoding^ Encoding {
    virtual System::Text::Encoding^ get(void) override {
        return nullptr;
    }
}