WIN32实现远程桌面监控

文章目录

- 完整代码
- - API简介
  - 调试代码
- 后记
- reference

完整代码

server.cpp

#include <winsock2.h>
#include <Ws2tcpip.h>
#include <windows.h>
#include <stdio.h>
#include <vector>
#pragma comment(lib, "ws2_32.lib")LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
void RenderBitmap(HDC hdc, BYTE* bBits, int width, int height, int windowWidth, int windowHeight);class xy {
public:int x;int y;
};int main(void)
{// Initialize WinSockWSADATA wsaData;WSAStartup(MAKEWORD(2, 2), &wsaData);SOCKET serverSocket = socket(AF_INET, SOCK_STREAM, 0);sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_port = htons(8888);  // Port numberinet_pton(AF_INET, "127.0.0.1", &serverAddr.sin_addr.s_addr);bind(serverSocket, (sockaddr*)&serverAddr, sizeof(serverAddr));listen(serverSocket, 5);// Wait for client connectionSOCKET clientSocket = accept(serverSocket, NULL, NULL);xy data;recv(clientSocket, (char*)&data, sizeof(data), 0);// Register window classWNDCLASS wc = { 0 };wc.lpfnWndProc = WndProc;wc.hInstance = GetModuleHandle(NULL);wc.lpszClassName = L"ScreenCaptureReceiverWindowClass";RegisterClass(&wc);// Set up the bitmap for renderingBITMAPINFO bInfo;HBITMAP hBitmap;BYTE* bBits = nullptr;int screenWidth = data.x;  // Set screen widthint screenHeight = data.y; // Set screen heightint windowWidth = 800;int windowHeight = 600;float screenAspect = (float)screenWidth / screenHeight;float windowAspect = (float)windowWidth / windowHeight;// Adjust window size to maintain the screen aspect ratioif (screenAspect > windowAspect){windowHeight = (INT)(windowWidth / screenAspect);}else{windowWidth = (INT)(windowHeight * screenAspect);}RECT rect = { 0, 0, windowWidth, windowHeight };AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, FALSE);ZeroMemory(&bInfo, sizeof(BITMAPINFO));bInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bInfo.bmiHeader.biBitCount = 24;bInfo.bmiHeader.biCompression = BI_RGB;bInfo.bmiHeader.biPlanes = 1;bInfo.bmiHeader.biWidth = screenWidth;bInfo.bmiHeader.biHeight = -screenHeight;  // Top-down HWND hwnd = CreateWindowEx(0, wc.lpszClassName, L"Screen Receiver", WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT, rect.right - rect.left, rect.bottom - rect.top, NULL, NULL, wc.hInstance, NULL);ShowWindow(hwnd, SW_SHOW);HDC hdc = GetDC(hwnd);hBitmap = CreateDIBSection(hdc, &bInfo, DIB_RGB_COLORS, (VOID**)&bBits, NULL, 0);// Main message loopMSG msg = { 0 };while (msg.message != WM_QUIT){if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)){TranslateMessage(&msg);DispatchMessage(&msg);}else{// Receive image data from the clientint len = screenWidth * screenHeight * 3;recv(clientSocket, (char*)bBits, len, 0);// Render the received bitmapRenderBitmap(hdc, bBits, screenWidth, screenHeight, windowWidth, windowHeight);Sleep(200);  // Adjust the refresh rate}}// Clean upDeleteObject(hBitmap);ReleaseDC(hwnd, hdc);closesocket(clientSocket);closesocket(serverSocket);WSACleanup();return 0;
}void RenderBitmap(HDC hdc, BYTE* bBits, int width, int height, int windowWidth, int windowHeight)
{BITMAPINFO bInfo;ZeroMemory(&bInfo, sizeof(BITMAPINFO));bInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bInfo.bmiHeader.biBitCount = 24;bInfo.bmiHeader.biCompression = BI_RGB;bInfo.bmiHeader.biPlanes = 1;bInfo.bmiHeader.biWidth = width;bInfo.bmiHeader.biHeight = -height;SetStretchBltMode(hdc, HALFTONE);StretchDIBits(hdc, 0, 0, windowWidth, windowHeight, 0, 0, width, height, bBits, &bInfo, DIB_RGB_COLORS, SRCCOPY);
}LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{switch (msg){case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hwnd, msg, wParam, lParam);}return 0;
}

client.cpp

#include <winsock2.h>
#include <Ws2tcpip.h>
#include <windows.h>
#include <vector>
#include<iostream>
#pragma comment(lib, "ws2_32.lib")
using namespace std;
std::vector<int> getxy();
class xyz {
public:int x;int y;
};
int main(void)
{// Initialize WinSockWSADATA wsaData;WSAStartup(MAKEWORD(2, 2), &wsaData);SOCKET clientSocket = socket(AF_INET, SOCK_STREAM, 0);sockaddr_in serverAddr;serverAddr.sin_family = AF_INET;serverAddr.sin_port = htons(8888);  // Port numberinet_pton(AF_INET, "127.0.0.1", &serverAddr.sin_addr.s_addr);// Replace with the server's IP addressconnect(clientSocket, (sockaddr*)&serverAddr, sizeof(serverAddr));// Get screen dimensionsvector<int> xy = getxy();int screenWidth = xy[0];int screenHeight = xy[1];xyz data;data.x = screenWidth;data.y = screenHeight;send(clientSocket, (char*)&data, sizeof(data), 0);// Set up the screen captureBITMAPINFO bInfo;HDC hDC, hMemDC;HBITMAP hBitmap;BYTE* bBits = NULL;hDC = GetDC(NULL);hMemDC = CreateCompatibleDC(hDC);ZeroMemory(&bInfo, sizeof(BITMAPINFO));bInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bInfo.bmiHeader.biBitCount = 24;bInfo.bmiHeader.biCompression = BI_RGB;bInfo.bmiHeader.biPlanes = 1;bInfo.bmiHeader.biWidth = screenWidth;bInfo.bmiHeader.biHeight = -screenHeight;hBitmap = CreateDIBSection(hDC, &bInfo, DIB_RGB_COLORS, (VOID**)&bBits, NULL, 0);SelectObject(hMemDC, hBitmap);int len = screenWidth * screenHeight * 3;// Main loop to capture and send screen datawhile (true){BitBlt(hMemDC, 0, 0, screenWidth, screenHeight, hDC, 0, 0, SRCCOPY);send(clientSocket, (char*)bBits, len, 0);Sleep(20);  // Adjust the sending rate}// Clean upDeleteObject(hBitmap);DeleteDC(hMemDC);ReleaseDC(NULL, hDC);closesocket(clientSocket);WSACleanup();return 0;
}std::vector<int> getxy() {HWND hWnd = GetDesktopWindow();//根据需要可以替换成自己程序的句柄 HMONITOR hMonitor = MonitorFromWindow(hWnd, MONITOR_DEFAULTTONEAREST);DEVMODE dm;MONITORINFOEX miex;dm.dmSize = sizeof(dm);dm.dmDriverExtra = 0;miex.cbSize = sizeof(miex);GetMonitorInfo(hMonitor, &miex);// 获取监视器物理宽度与高度EnumDisplaySettings(miex.szDevice, ENUM_CURRENT_SETTINGS, &dm);int cxPhysical = dm.dmPelsWidth;int cyPhysical = dm.dmPelsHeight;vector<int> ret;ret.push_back(cxPhysical);ret.push_back(cyPhysical);return ret;
}

效果展示

在这里插入图片描述

API简介

WSAStartup

int WSAAPI WSAStartup([in]  WORD      wVersionRequested,[out] LPWSADATA lpWSAData
);

wsastartup

初始化 Winsock 库：加载并初始化 Winsock 库的必要组件。
版本检查：应用程序可以通过 WSAStartup 指定所需的 Winsock 版本，同时函数会返回实际初始化的版本信息。
资源分配：为应用程序的网络操作分配必要的资源。

调用 WSAStartup 成功后，应用程序才能继续进行网络编程。当应用程序完成所有网络操作后，应调用 WSACleanup 函数来释放资源并终止 Winsock 使用。

inet_pton/inet_ntop

这两个函数是随IPv6出现的函数，对于IPv4地址和IPv6地址都适用，函数中p和n分别代表表达（presentation)和数值（numeric)。地址的表达格式通常是ASCII字符串，数值格式则是存放到套接字地址结构的二进制值。
int inet_pton(int family, const char *strptr, void *addrptr);     
const char * inet_ntop(int family, const void *addrptr, char *strptr, size_t len);

StretchBlt /BitBlt/StretchDIBits

StretchBlt 和 BitBlt 是 Windows GDI（图形设备接口）中的两个函数，用于在设备上下文（Device Context，DC）之间进行位图的复制和绘制操作。它们的主要区别在于是否进行图像的缩放。StretchDIBits从 DIB 数据（通常存储在内存中）到设备上下文进行更灵活的图像处理

调试代码

屏幕截屏

#include<stdio.h>
#include<windows.h>
#include<string>
#include<iostream>
using namespace std;
int main(void)
{BITMAPFILEHEADER bfHeader;BITMAPINFOHEADER biHeader;BITMAPINFO bInfo;HGDIOBJ hTempBitmap;HBITMAP hBitmap;BITMAP bAllDesktops;HDC hDC, hMemDC;LONG lWidth, lHeight;BYTE* bBits = NULL;HANDLE hHeap = GetProcessHeap();DWORD cbBits, dwWritten = 0;HANDLE hFile;INT x = GetSystemMetrics(SM_XVIRTUALSCREEN);INT y = GetSystemMetrics(SM_YVIRTUALSCREEN);ZeroMemory(&bfHeader, sizeof(BITMAPFILEHEADER));ZeroMemory(&biHeader, sizeof(BITMAPINFOHEADER));ZeroMemory(&bInfo, sizeof(BITMAPINFO));ZeroMemory(&bAllDesktops, sizeof(BITMAP));hDC = GetDC(NULL);hTempBitmap = GetCurrentObject(hDC, OBJ_BITMAP);GetObjectW(hTempBitmap, sizeof(BITMAP), &bAllDesktops);lWidth = bAllDesktops.bmWidth;lHeight = bAllDesktops.bmHeight;//get lWidth lHeightDeleteObject(hTempBitmap);bfHeader.bfType = (WORD)('B' | ('M' << 8));//小端存储BMbfHeader.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);biHeader.biSize = sizeof(BITMAPINFOHEADER);biHeader.biBitCount = 24;biHeader.biCompression = BI_RGB;biHeader.biPlanes = 1;biHeader.biWidth = lWidth;biHeader.biHeight = lHeight;bInfo.bmiHeader = biHeader;cbBits = (((24 * lWidth + 31) & ~31) / 8) * lHeight;//~31 相当于将最低 5 位全置为 0，保证是32的倍数(四字节对齐)hMemDC = CreateCompatibleDC(hDC);hBitmap = CreateDIBSection(hDC, &bInfo, DIB_RGB_COLORS, (VOID**)&bBits, NULL, 0);SelectObject(hMemDC, hBitmap);BitBlt(hMemDC, 0, 0, lWidth, lHeight, hDC, x, y, SRCCOPY);string path = "D:\\c_project\\dlltest\\a.bmp";hFile = CreateFileA(path.c_str(), GENERIC_WRITE | GENERIC_READ, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL,NULL);if (INVALID_HANDLE_VALUE == hFile){DeleteDC(hMemDC);ReleaseDC(NULL, hDC);DeleteObject(hBitmap);return FALSE;}WriteFile(hFile, &bfHeader, sizeof(BITMAPFILEHEADER), &dwWritten, NULL);WriteFile(hFile, &biHeader, sizeof(BITMAPINFOHEADER), &dwWritten, NULL);WriteFile(hFile, bBits, cbBits, &dwWritten, NULL);FlushFileBuffers(hFile);CloseHandle(hFile);DeleteDC(hMemDC);ReleaseDC(NULL, hDC);DeleteObject(hBitmap);return TRUE;
}

保存的时刻为代码运行到BitBlt时刻的图像

本地实时渲染

#include <windows.h>
#include <stdio.h>
#include <string>
#include <iostream>
#include<vector>
using namespace std;LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
std::vector<int> getxy();
int main(void)
{// Register window classWNDCLASS wc = { 0 };wc.lpfnWndProc = WndProc;wc.hInstance = GetModuleHandle(NULL);wc.lpszClassName = L"ScreenCaptureWindowClass";RegisterClass(&wc);// Get screen dimensionsvector<int> xy = getxy();int screenWidth = xy[0];int screenHeight = xy[1];// Define the desired window size (e.g., 800x600)INT windowWidth = 800;INT windowHeight = 600;// Calculate aspect ratiosfloat screenAspect = (float)screenWidth / screenHeight;float windowAspect = (float)windowWidth / windowHeight;// Adjust window size to maintain the screen aspect ratioif (screenAspect > windowAspect){windowHeight = (INT)(windowWidth / screenAspect);}else{windowWidth = (INT)(windowHeight * screenAspect);}// Calculate window size including borders and title barRECT rect = { 0, 0, windowWidth, windowHeight };AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, FALSE);// Create windowHWND hwnd = CreateWindowEx(0, wc.lpszClassName, L"Screen Capture", WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT, rect.right - rect.left, rect.bottom - rect.top, NULL, NULL, wc.hInstance, NULL);ShowWindow(hwnd, SW_SHOW);// Set up the screen captureBITMAPINFO bInfo;HDC hDC, hMemDC;HBITMAP hBitmap;BYTE* bBits = NULL;hDC = GetDC(NULL);hMemDC = CreateCompatibleDC(hDC);ZeroMemory(&bInfo, sizeof(BITMAPINFO));bInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bInfo.bmiHeader.biBitCount = 24;bInfo.bmiHeader.biCompression = BI_RGB;bInfo.bmiHeader.biPlanes = 1;bInfo.bmiHeader.biWidth = screenWidth;bInfo.bmiHeader.biHeight = -screenHeight;  // Negative height to indicate top-down DIBhBitmap = CreateDIBSection(hDC, &bInfo, DIB_RGB_COLORS, (VOID**)&bBits, NULL, 0);SelectObject(hMemDC, hBitmap);// Main message loopMSG msg = { 0 };while (msg.message != WM_QUIT){if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)){TranslateMessage(&msg);DispatchMessage(&msg);}else{// Capture the screenBitBlt(hMemDC, 0, 0, screenWidth, screenHeight, hDC, 0, 0, SRCCOPY);// Get the device context of the windowHDC hWindowDC = GetDC(hwnd);// Scale and paint the captured screen to fit the window sizeSetStretchBltMode(hWindowDC, HALFTONE);StretchBlt(hWindowDC, 0, 0, windowWidth, windowHeight, hMemDC, 0, 0, screenWidth, screenHeight, SRCCOPY);ReleaseDC(hwnd, hWindowDC);// Sleep for 0.2 seconds (200 milliseconds)//Sleep(200);}}// Clean upDeleteObject(hBitmap);DeleteDC(hMemDC);ReleaseDC(NULL, hDC);return 0;
}LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{switch (msg){case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hwnd, msg, wParam, lParam);}return 0;
}
std::vector<int> getxy() {HWND hWnd = GetDesktopWindow();//根据需要可以替换成自己程序的句柄 HMONITOR hMonitor = MonitorFromWindow(hWnd, MONITOR_DEFAULTTONEAREST);DEVMODE dm;MONITORINFOEX miex;dm.dmSize = sizeof(dm);dm.dmDriverExtra = 0;miex.cbSize = sizeof(miex);GetMonitorInfo(hMonitor, &miex);// 获取监视器物理宽度与高度EnumDisplaySettings(miex.szDevice, ENUM_CURRENT_SETTINGS, &dm);int cxPhysical = dm.dmPelsWidth;int cyPhysical = dm.dmPelsHeight;vector<int> ret;ret.push_back(cxPhysical);ret.push_back(cyPhysical);return ret;
}

传输渲染

#include <windows.h>
#include <stdio.h>
#include <string>
#include <iostream>
#include<vector>
using namespace std;LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
std::vector<int> getxy();int main(void)
{// Register window classWNDCLASS wc = { 0 };wc.lpfnWndProc = WndProc;wc.hInstance = GetModuleHandle(NULL);wc.lpszClassName = L"ScreenCaptureWindowClass";RegisterClass(&wc);// Get screen dimensionsvector<int> xy = getxy();int screenWidth = xy[0];int screenHeight = xy[1];// Define the desired window size (e.g., 800x600)INT windowWidth = 800;INT windowHeight = 600;// Calculate aspect ratiosfloat screenAspect = (float)screenWidth / screenHeight;float windowAspect = (float)windowWidth / windowHeight;// Adjust window size to maintain the screen aspect ratioif (screenAspect > windowAspect){windowHeight = (INT)(windowWidth / screenAspect);}else{windowWidth = (INT)(windowHeight * screenAspect);}// Calculate window size including borders and title barRECT rect = { 0, 0, windowWidth, windowHeight };AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, FALSE);// Create windowHWND hwnd = CreateWindowEx(0, wc.lpszClassName, L"Screen Capture", WS_OVERLAPPEDWINDOW,CW_USEDEFAULT, CW_USEDEFAULT, rect.right - rect.left, rect.bottom - rect.top, NULL, NULL, wc.hInstance, NULL);ShowWindow(hwnd, SW_SHOW);// Set up the screen captureBITMAPINFO bInfo;HDC hDC, hMemDC;HBITMAP hBitmap;BYTE* bBits = NULL;hDC = GetDC(NULL);hMemDC = CreateCompatibleDC(hDC);ZeroMemory(&bInfo, sizeof(BITMAPINFO));bInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);bInfo.bmiHeader.biBitCount = 24;bInfo.bmiHeader.biCompression = BI_RGB;bInfo.bmiHeader.biPlanes = 1;bInfo.bmiHeader.biWidth = screenWidth;bInfo.bmiHeader.biHeight = -screenHeight;  // Negative height to indicate top-down DIBhBitmap = CreateDIBSection(hDC, &bInfo, DIB_RGB_COLORS, (VOID**)&bBits, NULL, 0);SelectObject(hMemDC, hBitmap);int len = screenWidth * screenHeight * 3;// Allocate a buffer for storing the screen dataBYTE* screenBuffer = new BYTE[len]; // 24-bit color// Main message loopMSG msg = { 0 };while (msg.message != WM_QUIT){if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)){TranslateMessage(&msg);DispatchMessage(&msg);}else{// Capture the screen into bufferBitBlt(hMemDC, 0, 0, screenWidth, screenHeight, hDC, 0, 0, SRCCOPY);memcpy(screenBuffer, bBits, len); // Copy screen data to buffer// Get the device context of the windowHDC hWindowDC = GetDC(hwnd);// Create a compatible bitmap from buffer dataHBITMAP hBufferBitmap = CreateCompatibleBitmap(hWindowDC, screenWidth, screenHeight);HDC hBufferDC = CreateCompatibleDC(hWindowDC);SelectObject(hBufferDC, hBufferBitmap);// Copy buffer data into the bitmapSetDIBits(hBufferDC, hBufferBitmap, 0, screenHeight, screenBuffer, &bInfo, DIB_RGB_COLORS);// Scale and paint the buffered screen to fit the window sizeSetStretchBltMode(hWindowDC, HALFTONE);StretchBlt(hWindowDC, 0, 0, windowWidth, windowHeight, hBufferDC, 0, 0, screenWidth, screenHeight, SRCCOPY);// Clean upDeleteObject(hBufferBitmap);DeleteDC(hBufferDC);ReleaseDC(hwnd, hWindowDC);// Sleep for 0.2 seconds (200 milliseconds)Sleep(200);}}// Clean updelete[] screenBuffer;DeleteObject(hBitmap);DeleteDC(hMemDC);ReleaseDC(NULL, hDC);return 0;
}LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{switch (msg){case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hwnd, msg, wParam, lParam);}return 0;
}std::vector<int> getxy() {HWND hWnd = GetDesktopWindow();//根据需要可以替换成自己程序的句柄 HMONITOR hMonitor = MonitorFromWindow(hWnd, MONITOR_DEFAULTTONEAREST);DEVMODE dm;MONITORINFOEX miex;dm.dmSize = sizeof(dm);dm.dmDriverExtra = 0;miex.cbSize = sizeof(miex);GetMonitorInfo(hMonitor, &miex);// 获取监视器物理宽度与高度EnumDisplaySettings(miex.szDevice, ENUM_CURRENT_SETTINGS, &dm);int cxPhysical = dm.dmPelsWidth;int cyPhysical = dm.dmPelsHeight;vector<int> ret;ret.push_back(cxPhysical);ret.push_back(cyPhysical);return ret;
}

参数传递

// 发送结构体
xy data;
data.x = 10;
data.y = 20;
send(clientSocket, (char *) & data, sizeof(data), 0);//接受结构体xy data;recv(clientSocket, (char*) & data, sizeof(data), 0);std::cout << "Received: x = " << data.x << ", y = " << data.y << std::endl;

后记

BitBlt (Bit Block Transfer)

BitBlt 函数用于从一个设备上下文复制一个位图区域到另一个设备上下文。它不进行任何缩放操作，原样复制位图。通常用于在同一尺寸的区域之间移动或绘制位图。

函数原型：

cpp复制代码BOOL BitBlt(HDC   hdcDest,   // 目标设备上下文句柄int   nXDest,    // 目标矩形左上角的 X 坐标int   nYDest,    // 目标矩形左上角的 Y 坐标int   nWidth,    // 目标矩形的宽度int   nHeight,   // 目标矩形的高度HDC   hdcSrc,    // 源设备上下文句柄int   nXSrc,     // 源矩形左上角的 X 坐标int   nYSrc,     // 源矩形左上角的 Y 坐标DWORD dwRop      // 光栅操作代码
);

主要特性：

复制图像：从源设备上下文复制图像到目标设备上下文，不进行缩放。
位块传输：按照指定的矩形区域进行传输。

应用场景：

同尺寸位图：适用于源和目标位图区域尺寸相同的情况下的快速复制操作。
简单绘制：用于简单的图像绘制、窗口背景绘制等。

StretchBlt (Stretch Bit Block Transfer)

StretchBlt 函数与 BitBlt 类似，但它可以在复制位图时进行缩放。目标区域和源区域的大小可以不同，StretchBlt 会自动调整图像的尺寸，使之适应目标矩形。

函数原型：

cpp复制代码BOOL StretchBlt(HDC   hdcDest,     // 目标设备上下文句柄int   nXOriginDest,// 目标矩形左上角的 X 坐标int   nYOriginDest,// 目标矩形左上角的 Y 坐标int   nWidthDest,  // 目标矩形的宽度int   nHeightDest, // 目标矩形的高度HDC   hdcSrc,      // 源设备上下文句柄int   nXOriginSrc, // 源矩形左上角的 X 坐标int   nYOriginSrc, // 源矩形左上角的 Y 坐标int   nWidthSrc,   // 源矩形的宽度int   nHeightSrc,  // 源矩形的高度DWORD dwRop        // 光栅操作代码
);

主要特性：

缩放图像：支持对位图进行缩放，目标区域可以比源区域大或小。
比例变换：自动调整图像比例，使其适应目标区域。

应用场景：

图像缩放：用于在图像渲染时需要缩放、拉伸或压缩的场景，如缩略图显示、窗口大小变化时的图像调整等。
动态布局：在需要根据设备上下文的大小动态调整图像显示时，StretchBlt 是合适的选择。

总结

BitBlt：直接复制图像，不进行缩放，适合源和目标区域大小一致的情况下。
StretchBlt：支持缩放，在复制图像时根据需要调整尺寸，适合在不同大小区域之间传输图像的场景。

字符转化

class Char {
public:static std::wstring AtoW(const std::string& str){int wcLen = MultiByteToWideChar(CP_ACP, 0, str.c_str(), -1, NULL, 0);std::wstring newBuf;newBuf.resize(wcLen);MultiByteToWideChar(CP_ACP, 0, str.c_str(), -1, (LPWSTR)newBuf.c_str(), wcLen);return newBuf;}static std::string WtoA(const std::wstring& str){int cLen = WideCharToMultiByte(CP_ACP, 0, str.c_str(), -1, NULL, 0, 0, NULL);std::string newBuf;newBuf.resize(cLen);WideCharToMultiByte(CP_ACP, 0, str.c_str(), -1, (char*)newBuf.c_str(), cLen, 0, NULL);return newBuf;}
};

reference

https://geocld.github.io/2021/03/02/bmp/