Excel(.xls)の読み書きについて

    public ref class Form1 : public System::Windows::Forms::Form
    {

        ：
        略
        ：

    private:
        System::Void button1_Click(System::Object^ sender, System::EventArgs^ e) {
            Excel::Application^ xlApplication = nullptr;
            
            try {
                xlApplication = gcnew Excel::Application();
                xlApplication->Visible = true;
                Excel::Workbooks^ xlWorkbooks = nullptr;

                try {
                    xlWorkbooks = xlApplication->Workbooks;
                    Excel::Workbook^ xlWorkbook = nullptr;

                    try {
                        xlWorkbook = xlWorkbooks->Add(System::Reflection::Missing::Value);
                    } finally {
                        if (xlWorkbook != nullptr) {
                            System::Runtime::InteropServices::Marshal::ReleaseComObject(xlWorkbook);
                        }
                    }
                } finally {
                    if (xlWorkbooks != nullptr) {
                        System::Runtime::InteropServices::Marshal::ReleaseComObject(xlWorkbooks);
                    }
                }
            } finally {
                if (xlApplication != nullptr) {
                    System::Runtime::InteropServices::Marshal::ReleaseComObject(xlApplication);
                }
            }
        }
    };