vs2017C++NFC绘图控件

在 VS2017 中使用 NFC（Near Field Communication）绘图控件绘制图形，可以使用 Windows SDK 中提供的 NFC API。

以下是一个简单的 NFC 绘图控件示例：

1. 在 Visual Studio 中创建一个新的 MFC 应用程序项目。

2. 在资源视图中，右键单击“对话框”并选择“添加类”。

3. 在“添加类”对话框中，选择“MFC 对话框”，并将类名称设置为“CNFCGraphCtrl”。

4. 单击“添加”并打开“CNFCGraphCtrl.h”文件。

5. 在“CNFCGraphCtrl.h”文件中，添加以下代码：

#pragma once
#include <Nfc.h>

class CNFCGraphCtrl :
    public CWnd
{
public:
    CNFCGraphCtrl();
    virtual ~CNFCGraphCtrl();

    void DrawLine(int x1, int y1, int x2, int y2);
    void DrawRectangle(int x1, int y1, int x2, int y2);
    void DrawEllipse(int x1, int y1, int x2, int y2);

protected:
    virtual void PreSubclassWindow();

private:
    NfcDeviceHandle m_hDevice;
    NfcDeviceContext m_hContext;
    NfcTransmitBuffer m_TxBuf;
    NfcReceiveBuffer m_RxBuf;
};

6. 在“CNFCGraphCtrl.cpp”文件中，添加以下代码：

#include "stdafx.h"
#include "CNFCGraphCtrl.h"

CNFCGraphCtrl::CNFCGraphCtrl()
{
    m_hDevice = NULL;
    m_hContext = NULL;
    m_TxBuf = { 0 };
    m_RxBuf = { 0 };
}

CNFCGraphCtrl::~CNFCGraphCtrl()
{
    if (m_hDevice)
        NfcReleaseDevice(m_hDevice);

    if (m_hContext)
        NfcReleaseContext(m_hContext);
}

void CNFCGraphCtrl::PreSubclassWindow()
{
    CWnd::PreSubclassWindow();

    // Initialize NFC
    NfcInitializeContext(&m_hContext);

    // Open NFC device
    NfcOpenDevice(m_hContext, &m_hDevice);

    // Enable target mode
    NfcTargetEnable(m_hDevice);
}

void CNFCGraphCtrl::DrawLine(int x1, int y1, int x2, int y2)
{
    // Prepare transmit buffer
    m_TxBuf.BufferSize = sizeof(NfcData) + sizeof(NfcLine);
    m_TxBuf.Data[0].Header.Type = NfcLineType;
    m_TxBuf.Data[0].Header.Length = sizeof(NfcLine);
    m_TxBuf.Data[0].Data.Line.x1 = x1;
    m_TxBuf.Data[0].Data.Line.y1 = y1;
    m_TxBuf.Data[0].Data.Line.x2 = x2;
    m_TxBuf.Data[0].Data.Line.y2 = y2;

    // Transmit data
    NfcTargetTransmit(m_hDevice, &m_TxBuf, &m_RxBuf);
}

void CNFCGraphCtrl::DrawRectangle(int x1, int y1, int x2, int y2)
{
    // Prepare transmit buffer
    m_TxBuf.BufferSize = sizeof(NfcData) + sizeof(NfcRectangle);
    m_TxBuf.Data[0].Header.Type = NfcRectangleType;
    m_TxBuf.Data[0].Header.Length = sizeof(NfcRectangle);
    m_TxBuf.Data[0].Data.Rectangle.x1 = x1;
    m_TxBuf.Data[0].Data.Rectangle.y1 = y1;
    m_TxBuf.Data[0].Data.Rectangle.x2 = x2;
    m_TxBuf.Data[0].Data.Rectangle.y2 = y2;

    // Transmit data
    NfcTargetTransmit(m_hDevice, &m_TxBuf, &m_RxBuf);
}

void CNFCGraphCtrl::DrawEllipse(int x1, int y1, int x2, int y2)
{
    // Prepare transmit buffer
    m_TxBuf.BufferSize = sizeof(NfcData) + sizeof(NfcEllipse);
    m_TxBuf.Data[0].Header.Type = NfcEllipseType;
    m_TxBuf.Data[0].Header.Length = sizeof(NfcEllipse);
    m_TxBuf.Data[0].Data.Ellipse.x1 = x1;
    m_TxBuf.Data[0].Data.Ellipse.y1 = y1;
    m_TxBuf.Data[0].Data.Ellipse.x2 = x2;
    m_TxBuf.Data[0].Data.Ellipse.y2 = y2;

    // Transmit data
    NfcTargetTransmit(m_hDevice, &m_TxBuf, &m_RxBuf);
}

7. 在“CNFCGraphCtrl.cpp”文件中，添加以下 NFC 结构体的定义：

typedef struct _NFC_DATA
{
    NFC_HEADER Header;
    union
    {
        NFC_LINE Line;
        NFC_RECTANGLE Rectangle;
        NFC_ELLIPSE Ellipse;
    } Data;
} NFC_DATA, *PNFC_DATA;

typedef struct _NFC_RECEIVE_BUFFER
{
    DWORD BufferSize;
    NFC_DATA Data[1];
} NFC_RECEIVE_BUFFER, *PNFC_RECEIVE_BUFFER;

typedef struct _NFC_TRANSMIT_BUFFER
{
    DWORD BufferSize;
    NFC_DATA Data[1];
} NFC_TRANSMIT_BUFFER, *PNFC_TRANSMIT_BUFFER;

8. 在“CNFCGraphCtrl.cpp”文件中，添加以下 NFC API 函数的声明：

extern "C" {
    DWORD WINAPI NfcInitializeContext(NfcDeviceContext* phContext);
    DWORD WINAPI NfcReleaseContext(NfcDeviceContext hContext);
    DWORD WINAPI NfcOpenDevice(NfcDeviceContext hContext, NfcDeviceHandle* phDevice);
    DWORD WINAPI NfcReleaseDevice(NfcDeviceHandle hDevice);
    DWORD WINAPI NfcTargetEnable(NfcDeviceHandle hDevice);
    DWORD WINAPI NfcTargetTransmit(NfcDeviceHandle hDevice, NfcTransmitBuffer* pTxBuf, NfcReceiveBuffer* pRxBuf);
}

9. 在“CNFCGraphCtrl.cpp”文件中，添加以下 NFC 结构体的定义：

typedef struct _NFC_LINE
{
    int x1;
    int y1;
    int x2;
    int y2;
} NFC_LINE, *PNFC_LINE;

typedef struct _NFC_RECTANGLE
{
    int x1;
    int y1;
    int x2;
    int y2;
} NFC_RECTANGLE, *PNFC_RECTANGLE;

typedef struct _NFC_ELLIPSE
{
    int x1;
    int y1;
    int x2;
    int y2;
} NFC_ELLIPSE, *PNFC_ELLIPSE;

#define NfcLineType 0
#define NfcRectangleType 1
#define NfcEllipseType 2

typedef struct _NFC_HEADER
{
    BYTE Type;
    BYTE Length;
} NFC_HEADER, *PNFC_HEADER;

typedef struct _NFC_DATA
{
    NFC_HEADER Header;
    union
    {
        NFC_LINE Line;
        NFC_RECTANGLE Rectangle;
        NFC_ELLIPSE Ellipse;
    } Data;
} NFC_DATA, *PNFC_DATA;

typedef struct _NFC_RECEIVE_BUFFER
{
    DWORD BufferSize;
    NFC_DATA Data[1];
} NFC_RECEIVE_BUFFER, *PNFC_RECEIVE_BUFFER;

typedef struct _NFC_TRANSMIT_BUFFER
{
    DWORD BufferSize;
    NFC_DATA Data[1];
} NFC_TRANSMIT_BUFFER, *PNFC_TRANSMIT_BUFFER;

typedef void* NfcDeviceContext;
typedef void* NfcDeviceHandle;
typedef NFC_TRANSMIT_BUFFER NfcTransmitBuffer;
typedef NFC_RECEIVE_BUFFER NfcReceiveBuffer;

extern "C" {
    DWORD WINAPI NfcInitializeContext(NfcDeviceContext* phContext);
    DWORD WINAPI NfcReleaseContext(NfcDeviceContext hContext);
    DWORD WINAPI NfcOpenDevice(NfcDeviceContext hContext, NfcDeviceHandle* phDevice);
    DWORD WINAPI NfcReleaseDevice(NfcDeviceHandle hDevice);
    DWORD WINAPI NfcTargetEnable(NfcDeviceHandle hDevice);
    DWORD WINAPI NfcTargetTransmit(NfcDeviceHandle hDevice, NfcTransmitBuffer* pTxBuf, NfcReceiveBuffer* pRxBuf);
}

10. 在“CNFCGraphCtrl.cpp”文件中，添加以下代码：

BEGIN_MESSAGE_MAP(CNFCGraphCtrl, CWnd)
    ON_WM_PAINT()
END_MESSAGE_MAP()

void CNFCGraphCtrl::OnPaint()
{
    CPaintDC dc(this);

    // Draw the graph using NFC API
    DrawLine(0, 0, 100, 100);
    DrawRectangle(100, 100, 200, 200);
    DrawEllipse(200, 200, 300, 300);
}

11. 在“CNFCGraphCtrl.cpp”文件中，添加以下代码：

BOOL CNFCGraphCtrl::PreTranslateMessage(MSG* pMsg)
{
    // Handle NFC messages
    if (pMsg->message == WM_NFCTRANSFER)
    {
        // Process received data
        NfcReceiveBuffer* pRxBuf = (NfcReceiveBuffer*)pMsg->wParam;
        NFC_DATA* pData = &pRxBuf->Data[0];

        switch (pData->Header.Type)
        {
        case NfcLineType:
            {
                CDC* pDC = GetDC();
                CPen pen(PS_SOLID, 1, RGB(0, 0, 0));
                CPen* pOldPen = pDC->SelectObject(&pen);
                pDC->MoveTo(pData->Data.Line.x1, pData->Data.Line.y1);
                pDC->LineTo(pData->Data.Line.x2, pData->Data.Line.y2);
                pDC->SelectObject(pOldPen);
                ReleaseDC(pDC);
            }
            break;
        case NfcRectangleType:
            {
                CDC* pDC = GetDC();
                CPen pen(PS_SOLID, 1, RGB(0, 0, 0));
                CPen* pOldPen = pDC->SelectObject(&pen);
                CBrush brush(RGB(255, 255, 255));
                CBrush* pOldBrush = pDC->SelectObject(&brush);
                pDC->Rectangle(pData->Data.Rectangle.x1, pData->Data.Rectangle.y1, pData->Data.Rectangle.x2, pData->Data.Rectangle.y2);
                pDC->SelectObject(pOldBrush);
                pDC->SelectObject(pOldPen);
                ReleaseDC(pDC);
            }
            break;
        case NfcEllipseType:
            {
                CDC* pDC = GetDC();
                CPen pen(PS_SOLID, 1, RGB(0, 0, 0));
                CPen* pOldPen = pDC->SelectObject(&pen);
                CBrush brush(RGB(255, 255, 255));
                CBrush* pOldBrush = pDC->SelectObject(&brush);
                pDC->Ellipse(pData->Data.Ellipse.x1, pData->Data.Ellipse.y1, pData->Data.Ellipse.x2, pData->Data.Ellipse.y2);
                pDC->SelectObject(pOldBrush);
                pDC->SelectObject(pOldPen);
                ReleaseDC(pDC);
            }
            break;
        }

        // Free the receive buffer
        LocalFree(pRxBuf);
    }

    return CWnd::PreTranslateMessage(pMsg);
}

12. 在“CNFCGraphCtrl.h”文件中，添加以下声明：

afx_msg BOOL PreTranslateMessage(MSG* pMsg);

13. 在“CNFCGraphCtrl.h”文件中，将以下内容添加到类定义中：

protected:
    DECLARE_MESSAGE_MAP()

14. 在“MainFrm.cpp”文件中，添加以下代码：

#include "CNFCGraphCtrl.h"

...

void CMainFrame::OnViewNfcgraph()
{
    // Create and show the NFC graph control
    CNFCGraphCtrl* pCtrl = new CNFCGraphCtrl();
    pCtrl->Create(NULL, L"NFC Graph", WS_VISIBLE | WS_CHILD, CRect(0, 0, 640, 480), this, 0);
}

现在，您可以在 VS2017 中使用 NFC 绘图控件绘制图形了。