首先是抓图服务：

ICaptureHelper.h

#pragma once#include <windows.h>#include <string>using std::string;class ICaptureHelper{public: virtual ~ICaptureHelper() {} virtual bool Init(const string& windowName) = 0; virtual bool Init(HWND hwnd) = 0; virtual void Cleanup() = 0; virtual bool RefreshWindow() = 0; virtual bool ChangeWindowHandle(const string& windowName) = 0; virtual bool ChangeWindowHandle(HWND hwnd) = 0; virtual bool Capture() = 0; virtual const RECT& GetWindowRect() const = 0; virtual const RECT& GetClientRect() const = 0; virtual int GetBitmapDataSize() const = 0; virtual HBITMAP GetBitmap() const = 0; virtual void* GetBitmapAddress() const = 0;};

CaptureService.h

#pragma once#include "ICaptureHelper.h"#include <map>using std::map;class CaptureService{public: CaptureService() = default; static CaptureService& GetInstance(); enum CaptureType { //使用CreateDIBSection抓图，速度快，但是无法抓取D3D等渲染的窗口 CreateDibSection = 0, //使用PrintWindow抓图，速度慢(16ms左右)，但是可以抓取D3D等渲染的窗口 PrintWindow }; bool RegisterCapture(string name, string windowName, CaptureType type = CreateDibSection); //注册抓图服务 bool RegisterCapture(string name, HWND hwnd, CaptureType type = CreateDibSection); //注册抓图服务 void UnRegisterCapture(string name); //注销抓图服务 bool IsRegister(string name); //获取是否已注册抓图服务 bool RefreshWindow(string name); //刷新窗口 bool ChangeWindowHandle(string name, string windowName); //修改窗口句柄 bool ChangeWindowHandle(string name, HWND hwnd); //修改窗口句柄 bool Capture(string name); //抓图 bool GetWindowRect(string name, RECT& winRect); //获取窗口尺寸 bool GetClientRect(string name, RECT& clientRect); //获取窗口客户区尺寸 bool GetBitmapDataSize(string name, int& bmpDataSize); //获取抓图数据大小 bool GetBitmap(string name, HBITMAP& bitmap); //获取窗口位图 bool GetBitmapAddress(string name, void** bitsPtr); //获取窗口位图地址 void Cleanup(); //清理所有抓图服务private: ~CaptureService();private: map<string, ICaptureHelper*> captureHelpers_;};

其次是抓图代码封装：

AbsCaptureHelper.h

#pragma once#include "ICaptureHelper.h"class AbsCaptureHelper : public ICaptureHelper{public: AbsCaptureHelper(); virtual ~AbsCaptureHelper(); bool Init(const string& windowName) override; bool Init(HWND hwnd) override; void Cleanup() override; bool RefreshWindow() override; bool ChangeWindowHandle(const string& windowName) override; bool ChangeWindowHandle(HWND hwnd) override; bool Capture() override; const RECT& GetWindowRect() const override { return windowRect_; } const RECT& GetClientRect() const override { return clientRect_; } int GetBitmapDataSize() const override { return bmpDataSize_; } HBITMAP GetBitmap() const override { return bitmap_; } void* GetBitmapAddress() const override { return bitsPtr_; }protected: virtual bool InitDC(const BITMAPINFO& bitmapInfo) = 0; virtual bool DoCapture() = 0;protected: HWND hwnd_; HDC scrDc_; HDC memDc_; HBITMAP bitmap_; HBITMAP oldBitmap_; void* bitsPtr_; RECT windowRect_; RECT clientRect_; int bmpDataSize_;};

AbsCaptureHelper.cpp

#include "stdafx.h"#include "AbsCaptureHelper.h"AbsCaptureHelper::AbsCaptureHelper() : hwnd_(nullptr) , scrDc_(nullptr) , memDc_(nullptr) , bitmap_(nullptr) , oldBitmap_(nullptr) , bitsPtr_(nullptr) , windowRect_{ 0, 0, 0, 0 } , clientRect_{ 0, 0, 0, 0 } , bmpDataSize_(0){}AbsCaptureHelper::~AbsCaptureHelper(){ AbsCaptureHelper::Cleanup();}bool AbsCaptureHelper::Init(const string& windowName){ const auto handle = ::FindWindowA(nullptr, windowName.c_str()); if (handle == nullptr) { return false; } return Init(handle);}bool AbsCaptureHelper::Init(HWND hwnd){ hwnd_ = hwnd; //获取窗口大小 if (!::GetWindowRect(hwnd_, &windowRect_) || !::GetClientRect(hwnd_, &clientRect_)) { return false; } const auto clientRectWidth = clientRect_.right - clientRect_.left; const auto clientRectHeight = clientRect_.bottom - clientRect_.top; bmpDataSize_ = clientRectWidth * clientRectHeight * 4; //位图信息 BITMAPINFO bitmapInfo; bitmapInfo.bmiHeader.biSize = sizeof(bitmapInfo); bitmapInfo.bmiHeader.biWidth = clientRectWidth; bitmapInfo.bmiHeader.biHeight = clientRectHeight; bitmapInfo.bmiHeader.biPlanes = 1; bitmapInfo.bmiHeader.biBitCount = 32; bitmapInfo.bmiHeader.biSizeImage = clientRectWidth * clientRectHeight; bitmapInfo.bmiHeader.biCompression = BI_RGB; return InitDC(bitmapInfo);}void AbsCaptureHelper::Cleanup(){ if (bitmap_ == nullptr) { return; } //删除用过的对象 ::SelectObject(memDc_, oldBitmap_); ::DeleteObject(bitmap_); ::DeleteDC(memDc_); ::ReleaseDC(hwnd_, scrDc_); hwnd_ = nullptr; scrDc_ = nullptr; memDc_ = nullptr; bitmap_ = nullptr; oldBitmap_ = nullptr; bitsPtr_ = nullptr;}bool AbsCaptureHelper::RefreshWindow(){ const auto hwnd = hwnd_; Cleanup(); return Init(hwnd);}bool AbsCaptureHelper::ChangeWindowHandle(const string& windowName){ Cleanup(); return Init(windowName);}bool AbsCaptureHelper::ChangeWindowHandle(HWND hwnd){ Cleanup(); return Init(hwnd);}bool AbsCaptureHelper::Capture(){ if (bitmap_ == nullptr || memDc_ == nullptr || scrDc_ == nullptr) { return false; } return DoCapture();}

DibCaptureHelper.h

#pragma once#include "AbsCaptureHelper.h"class DibCaptureHelper : public AbsCaptureHelper{public: DibCaptureHelper(); virtual ~DibCaptureHelper();protected: bool InitDC(const BITMAPINFO& bitmapInfo) override; bool DoCapture() override;private: bool saveBitmap_; int mockPageNumber; int bmpCount_;};

DibCaptureHelper.cpp

#include "stdafx.h"#include "DibCaptureHelper.h"#include <sstream>static int BmpCount = 0;static int BmpMaxCount = 50;DibCaptureHelper::DibCaptureHelper() : saveBitmap_(false) , mockPageNumber(++BmpCount) , bmpCount_(0){}DibCaptureHelper::~DibCaptureHelper(){}bool DibCaptureHelper::InitDC(const BITMAPINFO& bitmapInfo){ scrDc_ = ::GetWindowDC(hwnd_); memDc_ = ::CreateCompatibleDC(scrDc_); bitmap_ = ::CreateDIBSection(memDc_, &bitmapInfo, DIB_RGB_COLORS, &bitsPtr_, nullptr, 0); if (bitmap_ == nullptr) { ::DeleteDC(memDc_); ::ReleaseDC(hwnd_, scrDc_); return false; } oldBitmap_ = static_cast<HBITMAP>(::SelectObject(memDc_, bitmap_)); return true;}bool DibCaptureHelper::DoCapture(){ const auto clientRectWidth = clientRect_.right - clientRect_.left; const auto clientRectHeight = clientRect_.bottom - clientRect_.top; const auto ret = ::BitBlt( memDc_, 0, 0, clientRectWidth, clientRectHeight, scrDc_, 0, 0, SRCCOPY); return ret != 0;}

PrintCaptureHelper.h

#pragma once#include "AbsCaptureHelper.h"class PrintCaptureHelper : public AbsCaptureHelper{public: PrintCaptureHelper(); virtual ~PrintCaptureHelper();protected: bool InitDC(const BITMAPINFO& bitmapInfo) override; bool DoCapture() override;};

PrintCaptureHelper.cpp

#include "stdafx.h"#include "PrintCaptureHelper.h"PrintCaptureHelper::PrintCaptureHelper(){}PrintCaptureHelper::~PrintCaptureHelper(){}bool PrintCaptureHelper::InitDC(const BITMAPINFO& bitmapInfo){ scrDc_ = ::GetWindowDC(hwnd_); memDc_ = ::CreateCompatibleDC(scrDc_); bitmap_ = ::CreateDIBSection(scrDc_, &bitmapInfo, DIB_RGB_COLORS, &bitsPtr_, nullptr, 0); if (bitmap_ == nullptr) { ::DeleteDC(memDc_); ::ReleaseDC(hwnd_, scrDc_); return false; } oldBitmap_ = static_cast<HBITMAP>(::SelectObject(memDc_, bitmap_)); return true;}bool PrintCaptureHelper::DoCapture(){ const auto ret = ::PrintWindow(hwnd_, memDc_, PW_CLIENTONLY | PW_RENDERFULLCONTENT); return ret != 0;}

以上就是c++ 封装一个截图服务的详细内容，更多关于c++ 截图的资料请关注其它相关文章！