ATL / WTL / STL

#pragma once

namespace test4 {

    namespace System{};
    namespace System{namespace ComponentModel{}};
    namespace System{namespace Collections{}};
    namespace System{namespace Windows{namespace Forms{}}};
    namespace System{namespace Data{}};
    namespace System{namespace Drawing{}};

    public ref class Form1 : public System::Windows::Forms::Form
    {
    public:
        Form1(void)
        {
            InitializeComponent();

using namespace System;
    using namespace System::ComponentModel;
    using namespace System::Collections;
    using namespace System::Windows::Forms;
    using namespace System::Data;
    using namespace System::Drawing;

namespace System{};
    namespace System{namespace ComponentModel{}};
    namespace System{namespace Collections{}};
    namespace System{namespace Windows{namespace Forms{}}};
    namespace System{namespace Data{}};
    namespace System{namespace Drawing{}};

error : expected namespace name
 using namespace System;                         ^
 error : use of undeclared identifier 'System'
using namespace System::ComponentModel;
                 ^
 error : expected namespace name
     using namespace System::ComponentModel;
                              ^
 error : use of undeclared identifier 'System'
using namespace System::Collections;
                  ^
and so on....including buttons...

VScoder12 wrote:

So, I used the namespace with curly braces{} suggested somewhere on the net

VScoder12 wrote:

any suggestion?

// Form1.h 
#pragma once

namespace WinForm {

    using namespace System;
    using namespace System::ComponentModel;
    using namespace System::Collections;
    using namespace System::Windows::Forms;
    using namespace System::Data;
    using namespace System::Drawing;
    
    /// <summary>
    /// Summary for Form1
    /// </summary>
    public ref class Form1 : public System::Windows::Forms::Form
    {
    public:
        Form1(void)
        {
            InitializeComponent();
            //
            //TODO: Add the constructor code here
            //
        }
    
    protected:
        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        ~Form1()
        {
            if (components)
            {
                delete components;
            }
        }
    
    private:
        /// <summary>
        /// Required designer variable.
        /// </summary>
        System::ComponentModel::Container ^components;
        
        #pragma region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        void InitializeComponent(void)
        {
            this->components = gcnew System::ComponentModel::Container();
            this->Size = System::Drawing::Size(300,300);
            this->Text = L"Form1";
            this->Padding = System::Windows::Forms::Padding(0);
            this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
        }
    #pragma endregion
    };
}


// WinForm.cpp : main project file.

#include "stdafx.h"
#include "Form1.h"

using namespace WinForm;

[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
    // Enabling Windows XP visual effects before any controls are created
    Application::EnableVisualStyles();
    Application::SetCompatibleTextRenderingDefault(false); 
    
    // Create the main window and run it
    Application::Run(gcnew Form1());
    return 0;
}

VScoder12 wrote:

clang compiler