使用VC++6.0用鼠标左键确定四个控制点，画出控制线，然后鼠标右键分别绘制三次Bezier曲线和三次B样条曲线。

以下是使用MFC和VC++6.0实现的代码：

#include "stdafx.h"
#include "BezierBsplines.h"
#include "math.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

#define MAX_CONTROL_POINTS 4
#define MAX_CURVE_POINTS 200
#define BEZIER_CURVE 0
#define BSPLINE_CURVE 1

/////////////////////////////////////////////////////////////////////////////
// CBezierBsplinesApp

BEGIN_MESSAGE_MAP(CBezierBsplinesApp, CWinApp)
    //{{AFX_MSG_MAP(CBezierBsplinesApp)
    // NOTE - the ClassWizard will add and remove mapping macros here.
    //    DO NOT EDIT what you see in these blocks of generated code !
    ON_COMMAND(ID_HELP, CWinApp::OnHelp)
    ON_WM_LBUTTONDOWN()
    ON_WM_RBUTTONDOWN()
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CBezierBsplinesApp construction

CBezierBsplinesApp::CBezierBsplinesApp()
{
    // TODO: add construction code here,
    // Place all significant initialization in InitInstance
}

/////////////////////////////////////////////////////////////////////////////
// The one and only CBezierBsplinesApp object

CBezierBsplinesApp theApp;

/////////////////////////////////////////////////////////////////////////////
// CBezierBsplinesApp initialization

BOOL CBezierBsplinesApp::InitInstance()
{
    // Standard initialization
    // If you are not using these features and wish to reduce the size
    //  of your final executable, you should remove from the following
    //  the specific initialization routines you do not need.

#ifdef _AFXDLL
    Enable3dControls();			// Call this when using MFC in a shared DLL
#else
    Enable3dControlsStatic();	// Call this when linking to MFC statically
#endif

    CBezierBsplinesDlg dlg;
    m_pMainWnd = &dlg;
    int nResponse = dlg.DoModal();
    if (nResponse == IDOK)
    {
        // TODO: Place code here to handle when the dialog is
        //  dismissed with OK
    }
    else if (nResponse == IDCANCEL)
    {
        // TODO: Place code here to handle when the dialog is
        //  dismissed with Cancel
    }

    // Since the dialog has been closed, return FALSE so that we exit the
    //  application, rather than start the application's message pump.
    return FALSE;
}

void CBezierBsplinesApp::OnLButtonDown(UINT nFlags, CPoint point) 
{
    // TODO: Add your message handler code here and/or call default
    static int curPoint = 0;
    if (curPoint < MAX_CONTROL_POINTS)
    {
        m_controlPoints[curPoint++] = point;
        DrawControlPoints();
    }
    CWinApp::OnLButtonDown(nFlags, point);
}

void CBezierBsplinesApp::DrawControlPoints()
{
    // Draw all control points
    CClientDC dc(m_pMainWnd);
    CBrush brush;
    brush.CreateSolidBrush(RGB(0, 0, 255));
    CBrush* pOldBrush = dc.SelectObject(&brush);
    for (int i = 0; i < MAX_CONTROL_POINTS; i++)
    {
        dc.Ellipse(m_controlPoints[i].x - 2, m_controlPoints[i].y - 2, m_controlPoints[i].x + 2, m_controlPoints[i].y + 2);
    }
    dc.SelectObject(pOldBrush);

    // Draw control lines
    CPen pen;
    pen.CreatePen(PS_SOLID, 1, RGB(0, 255, 0));
    CPen* pOldPen = dc.SelectObject(&pen);
    dc.MoveTo(m_controlPoints[0]);
    for (int i = 1; i < MAX_CONTROL_POINTS; i++)
    {
        dc.LineTo(m_controlPoints[i]);
    }
    dc.SelectObject(pOldPen);
}

void CBezierBsplinesApp::OnRButtonDown(UINT nFlags, CPoint point) 
{
    // TODO: Add your message handler code here and/or call default
    static int curveType = BEZIER_CURVE;
    if (curveType == BEZIER_CURVE)
    {
        DrawBezierCurve();
    }
    else if (curveType == BSPLINE_CURVE)
    {
        DrawBSplineCurve();
    }
    curveType = (curveType + 1) % 2;
    CWinApp::OnRButtonDown(nFlags, point);
}

void CBezierBsplinesApp::DrawBezierCurve()
{
    // Draw Bezier curve
    CClientDC dc(m_pMainWnd);
    CPen pen;
    pen.CreatePen(PS_SOLID, 1, RGB(255, 0, 0));
    CPen* pOldPen = dc.SelectObject(&pen);
    for (int i = 0; i < MAX_CURVE_POINTS; i++)
    {
        double t = (double)i / (MAX_CURVE_POINTS - 1);
        CPoint pt = CalculateBezierPoint(t);
        if (i == 0)
        {
            dc.MoveTo(pt);
        }
        else
        {
            dc.LineTo(pt);
        }
    }
    dc.SelectObject(pOldPen);
}

void CBezierBsplinesApp::DrawBSplineCurve()
{
    // Draw B-spline curve
    CClientDC dc(m_pMainWnd);
    CPen pen;
    pen.CreatePen(PS_SOLID, 1, RGB(255, 0, 0));
    CPen* pOldPen = dc.SelectObject(&pen);
    for (int i = 0; i < MAX_CURVE_POINTS; i++)
    {
        double t = (double)i / (MAX_CURVE_POINTS - 1);
        CPoint pt = CalculateBSplinePoint(t);
        if (i == 0)
        {
            dc.MoveTo(pt);
        }
        else
        {
            dc.LineTo(pt);
        }
    }
    dc.SelectObject(pOldPen);
}

CPoint CBezierBsplinesApp::CalculateBezierPoint(double t)
{
    // Calculate Bezier point
    CPoint pt;
    pt.x = (int)(pow(1 - t, 3) * m_controlPoints[0].x +
                 3 * t * pow(1 - t, 2) * m_controlPoints[1].x +
                 3 * pow(t, 2) * (1 - t) * m_controlPoints[2].x +
                 pow(t, 3) * m_controlPoints[3].x);
    pt.y = (int)(pow(1 - t, 3) * m_controlPoints[0].y +
                 3 * t * pow(1 - t, 2) * m_controlPoints[1].y +
                 3 * pow(t, 2) * (1 - t) * m_controlPoints[2].y +
                 pow(t, 3) * m_controlPoints[3].y);
    return pt;
}

CPoint CBezierBsplinesApp::CalculateBSplinePoint(double t)
{
    // Calculate B-spline point
    CPoint pt;
    double b0 = pow(1 - t, 3) / 6;
    double b1 = (3 * pow(t, 3) - 6 * pow(t, 2) + 4) / 6;
    double b2 = (-3 * pow(t, 3) + 3 * pow(t, 2) + 3 * t + 1) / 6;
    double b3 = pow(t, 3) / 6;
    pt.x = (int)(b0 * m_controlPoints[0].x +
                 b1 * m_controlPoints[1].x +
                 b2 * m_controlPoints[2].x +
                 b3 * m_controlPoints[3].x);
    pt.y = (int)(b0 * m_controlPoints[0].y +
                 b1 * m_controlPoints[1].y +
                 b2 * m_controlPoints[2].y +
                 b3 * m_controlPoints[3].y);
    return pt;
}

这里的`CBezierBsplinesDlg`是使用MFC的对话框类，可以使用Visual Studio创建。

在对话框类的`OnInitDialog()`函数中，我们可以添加以下代码：

// Initialize control points
m_controlPoints[0] = CPoint(100, 100);
m_controlPoints[1] = CPoint(150, 200);
m_controlPoints[2] = CPoint(250, 200);
m_controlPoints[3] = CPoint(300, 100);

// Draw control points
DrawControlPoints();

这里我们初始化了四个控制点，并且调用`DrawControlPoints()`函数绘制控制点和控制线。

在`OnLButtonDown()`函数中，我们处理鼠标左键按下事件，如果当前控制点数量小于4，则将当前鼠标位置作为一个新的控制点，并调用`DrawControlPoints()`函数重新绘制控制点和控制线。

在`OnRButtonDown()`函数中，我们处理鼠标右键按下事件，根据当前曲线类型（Bezier曲线或B样条曲线），调用对应的函数`DrawBezierCurve()`或`DrawBSplineCurve()`绘制曲线，并将曲线类型切换为下一个类型。

在`DrawBezierCurve()`和`DrawBSplineCurve()`函数中，我们分别使用`CalculateBezierPoint()`和`CalculateBSplinePoint()`函数计算曲线上的点，并使用`CClientDC`和`CPen`绘制曲线。

在`CalculateBezierPoint()`函数中，我们使用Bezier曲线的公式计算曲线上的点。

在`CalculateBSplinePoint()`函数中，我们使用B样条曲线的公式计算曲线上的点。

最后，我们在`CBezierBsplinesApp`类中定义了`m_controlPoints`数组存储四个控制点，在`DrawControlPoints()`函数中绘制控制点和控制线，在`CalculateBezierPoint()`函数和`CalculateBSplinePoint()`函数中计算曲线上的点。