未看到包含的头文件

编辑：新文件。我在访问Form1类中的公共函数时遇到问题。当我尝试使用标识符时，却找不到它。表格1:

#pragma once
#include "OpenGL.h"
#include "serialcom.h"
#include "calculations.h"
namespace GUI_1 {
    using namespace System;
    using namespace System::ComponentModel;
    using namespace System::Collections;
    using namespace System::Windows::Forms;
    using namespace System::Data;
    using namespace System::Drawing;
    using namespace OpenGLForm;

    /// <summary>
    /// Summary for Form1
    /// </summary>
    public ref class Form1 : public System::Windows::Forms::Form
    {
    public:
        Form1(void)
        {
            InitializeComponent();
            OpenGL = gcnew COpenGL(this->panel4, this->label16, 785, 530);
        }
        void changelabel2(float num)
        {
            label2 -> Text = " " + num;
        }
    protected: ...

OpenGL.h:

#include "stdafx.h"
#ifndef opengl
#define opengl
#pragma comment(lib, "opengl32.lib")
#pragma comment(lib, "glu32.lib")
#include <windows.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>
#include <math.h>
// Declare globals
...
using namespace System::Windows::Forms;
namespace OpenGLForm 
{
    public ref class COpenGL: public System::Windows::Forms::NativeWindow
    {
    public:
        COpenGL(System::Windows::Forms::Panel ^ parentForm, System::Windows::Forms::Label ^ lbl, GLsizei iWidth, GLsizei iHeight)
        {
            CreateParams^ cp = gcnew CreateParams;
            c_p_v v1, v2;
            changelabel2(189); 
...

所以这不起作用（上面，在"changelabel2"中）。也许是因为我没有使用类名？

这是我的主要：

#include "stdafx.h"
#include <string.h>
#include <iostream>
#include <stdio.h>
#include < vcclr.h >
#include < stdio.h >
#include < stdlib.h >
#include < vcclr.h >    
#include "Form1.h"
#include "calculations.h"
#include "serialcom.h"
using namespace GUI_1;
[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
    Form1^ form = gcnew Form1();
    Application::Run(form);
    return 0;
}

调用form.changelabel2也不起作用。