用于将指定DC保存为BMP位图，适用于暴露自身表面的动态程序情况捕捉。
// hdctobmpX.h : ChdctobmpX 的声明
#pragma once
#include "resource.h" // 主符号
// IhdctobmpX
[
object,
uuid("7C3141C9-A96E-4775-93C7-FEE42C738B94"),
dual, helpstring("IhdctobmpX 接口"),
pointer_default(unique)
]
__interface IhdctobmpX : IDispatch
{
[propput, id(1), helpstring("属性 HWND")] HRESULT HWND([in] ULONG newVal);
[propput, id(2), helpstring("属性 savepath")] HRESULT savepath([in] BSTR newVal);
[id(3), helpstring("方法savetobmp")] HRESULT savetobmp(void);
[propput, id(4), helpstring("属性 bwidth")] HRESULT bwidth([in] DOUBLE newVal);
[propput, id(5), helpstring("属性 bheight")] HRESULT bheight([in] DOUBLE newVal);
[id(6), helpstring("方法savetobmp2")] HRESULT savetobmp2(void);
};
// ChdctobmpX
[
coclass,
threading("apartment"),
vi_progid("HDCtoBMP.hdctobmpX"),
progid("HDCtoBMP.hdctobmpX.1"),
version(1.0),
uuid("F4A2F19D-AF6B-434A-A104-C4AA013E7B37"),
helpstring("hdctobmpX Class")
]
class ATL_NO_VTABLE ChdctobmpX :
public IhdctobmpX
{
protected:
//保存路径
_bstr_t m_path;
//传入句柄
HWND m_hwnd;
//位图宽
DOUBLE m_Width;
//位图高
DOUBLE m_Height;
public:
//构造
ChdctobmpX(){}
DECLARE_PROTECT_FINAL_CONSTRUCT()
HRESULT FinalConstruct(){return S_OK;}
//系构
void FinalRelease(){}
public:
//属性设置
STDMETHOD(put_HWND)(ULONG newVal);
STDMETHOD(put_savepath)(BSTR newVal);
//拷贝位图
STDMETHOD(savetobmp)(void);
STDMETHOD(put_bwidth)(DOUBLE newVal);
STDMETHOD(put_bheight)(DOUBLE newVal);
private:
PBITMAPINFO ChdctobmpX::CreateBitmapInfoStruct(HWND hwnd, HBITMAP hBmp);
void CreateBMPFile(HWND hwnd, LPTSTR pszFile, PBITMAPINFO pbi,HBITMAP hBMP, HDC hDC);
void Error( TCHAR * pText );
public:
STDMETHOD(savetobmp2)(void);
};
---------------------------------------------------------------------------------------------------------
// hdctobmpX.cpp : ChdctobmpX 的实现
#include "stdafx.h"
#include "hdctobmpX.h"
// ChdctobmpX
//存BMP
STDMETHODIMP ChdctobmpX::savetobmp(void)
{
// 设置图象保存位置加上.BMP扩展名
TCHAR m_ShortName[MAX_PATH];
wsprintf( m_ShortName, TEXT("%s.bmp\0"),(LPCTSTR)m_path);
//获取输入当前DC
HDC hdc=GetDC(this->m_hwnd);
//由当前DC转化创建一完备DC
HDC hdccmp = CreateCompatibleDC(hdc);
//由当前DC创建位图DC
HBITMAP hbmp = CreateCompatibleBitmap(hdc,m_Width, m_Height);
if (hbmp == 0) {return 0;}
//完备DC选择位图DC
if(!SelectObject(hdccmp, hbmp)){return 0;}
//当前DC拷贝到完备DC
BitBlt(hdccmp,0,0,m_Width, m_Height,hdc,0,0,SRCCOPY);
PBITMAPINFO pbi=CreateBitmapInfoStruct(this->m_hwnd ,hbmp);
CreateBMPFile(this->m_hwnd, m_ShortName,pbi,hbmp,hdccmp) ;
return S_OK;
}
STDMETHODIMP ChdctobmpX::savetobmp2(void)
{
// 设置图象保存位置加上.BMP扩展名
TCHAR m_ShortName[MAX_PATH];
wsprintf( m_ShortName, TEXT("%s.bmp\0"),(LPCTSTR)m_path);
//获取输入当前DC
HDC hdc=GetWindowDC(this->m_hwnd);
//由当前DC转化创建一完备DC
HDC hdccmp = CreateCompatibleDC(hdc);
//由当前DC创建位图DC
HBITMAP hbmp = CreateCompatibleBitmap(hdc,m_Width, m_Height);
if (hbmp == 0) {return 0;}
//完备DC选择位图DC
if(!SelectObject(hdccmp, hbmp)){return 0;}
//当前DC拷贝到完备DC
BitBlt(hdccmp,0,0,m_Width, m_Height,hdc,0,0,SRCCOPY);
PBITMAPINFO pbi=CreateBitmapInfoStruct(this->m_hwnd ,hbmp);
CreateBMPFile(this->m_hwnd, m_ShortName,pbi,hbmp,hdccmp) ;
return S_OK;
}
/////////////////////////////属性///////////////////////////
STDMETHODIMP ChdctobmpX::put_bwidth(DOUBLE newVal)
{
// TODO: 在此添加实现代码
this->m_Width=newVal;
return S_OK;
}
STDMETHODIMP ChdctobmpX::put_bheight(DOUBLE newVal)
{
// TODO: 在此添加实现代码
this->m_Height=newVal;
return S_OK;
}
STDMETHODIMP ChdctobmpX::put_savepath(BSTR newVal)
{
// TODO: 在此添加实现代码
this->m_path= newVal;
SysFreeString(newVal);
return S_OK;
}
STDMETHODIMP ChdctobmpX::put_HWND(ULONG newVal)
{
this->m_hwnd=(HWND)newVal;
return S_OK;
}
////////////////////////私有成员////////////////////////
//获取位图信息
PBITMAPINFO ChdctobmpX::CreateBitmapInfoStruct(HWND hwnd, HBITMAP hBmp)
{
BITMAP bmp;
PBITMAPINFO pbmi;
WORD cClrBits;
// Retrieve the bitmap color format, width, and height.
if (!GetObject(hBmp, sizeof(BITMAP), (LPSTR)&bmp))
Error("GetObject");
// Convert the color format to a count of bits.
cClrBits = (WORD)(bmp.bmPlanes * bmp.bmBitsPixel);
if (cClrBits == 1)
cClrBits = 1;
else if (cClrBits <= 4)
cClrBits = 4;
else if (cClrBits <= 8)
cClrBits = 8;
else if (cClrBits <= 16)
cClrBits = 16;
else if (cClrBits <= 24)
cClrBits = 24;
else cClrBits = 32;
// Allocate memory for the BITMAPINFO structure. (This structure
// contains a BITMAPINFOHEADER structure and an array of RGBQUAD
// data structures.)
if (cClrBits != 24)
pbmi = (PBITMAPINFO) LocalAlloc(LPTR,
sizeof(BITMAPINFOHEADER) +
sizeof(RGBQUAD) * (1<< cClrBits));
// There is no RGBQUAD array for the 24-bit-per-pixel format.
else
pbmi = (PBITMAPINFO) LocalAlloc(LPTR,
sizeof(BITMAPINFOHEADER));
// Initialize the fields in the BITMAPINFO structure.
pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
pbmi->bmiHeader.biWidth = bmp.bmWidth;
pbmi->bmiHeader.biHeight = bmp.bmHeight;
pbmi->bmiHeader.biPlanes = bmp.bmPlanes;
pbmi->bmiHeader.biBitCount = bmp.bmBitsPixel;
if (cClrBits < 24)
pbmi->bmiHeader.biClrUsed = (1<<cClrBits);
// If the bitmap is not compressed, set the BI_RGB flag.
pbmi->bmiHeader.biCompression = BI_RGB;
// Compute the number of bytes in the array of color
// indices and store the result in biSizeImage.
// For Windows NT, the width must be DWORD aligned unless
// the bitmap is RLE compressed. This example shows this.
// For Windows 95/98/Me, the width must be WORD aligned unless the
// bitmap is RLE compressed.
pbmi->bmiHeader.biSizeImage = ((pbmi->bmiHeader.biWidth * cClrBits +31) & ~31) /8
* pbmi->bmiHeader.biHeight;
// Set biClrImportant to 0, indicating that all of the
// device colors are important.
pbmi->bmiHeader.biClrImportant = 0;
return pbmi;
}
//写BMP文件
void ChdctobmpX::CreateBMPFile(HWND hwnd, LPTSTR pszFile, PBITMAPINFO pbi,HBITMAP hBMP, HDC hDC)
{
HANDLE hf; // file handle
BITMAPFILEHEADER hdr; // bitmap file-header
PBITMAPINFOHEADER pbih; // bitmap info-header
LPBYTE lpBits; // memory pointer
DWORD dwTotal; // total count of bytes
DWORD cb; // incremental count of bytes
BYTE *hp; // byte pointer
DWORD dwTmp;
pbih = (PBITMAPINFOHEADER) pbi;
lpBits = (LPBYTE) GlobalAlloc(GMEM_FIXED, pbih->biSizeImage);
if (!lpBits)
Error("GlobalAlloc");
// Retrieve the color table (RGBQUAD array) and the bits
// (array of palette indices) from the DIB.
if (!GetDIBits(hDC, hBMP, 0, (WORD) pbih->biHeight, lpBits, pbi,
DIB_RGB_COLORS))
{
Error("GetDIBits");
}
// Create the .BMP file.
hf = CreateFile(pszFile,
GENERIC_READ | GENERIC_WRITE,
(DWORD) 0,
NULL,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL,
(HANDLE) NULL);
if (hf == INVALID_HANDLE_VALUE)
Error("CreateFile");
hdr.bfType = 0x4d42; // 0x42 = "B" 0x4d = "M"
// Compute the size of the entire file.
hdr.bfSize = (DWORD) (sizeof(BITMAPFILEHEADER) +
pbih->biSize + pbih->biClrUsed
* sizeof(RGBQUAD) + pbih->biSizeImage);
hdr.bfReserved1 = 0;
hdr.bfReserved2 = 0;
// Compute the offset to the array of color indices.
hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) +
pbih->biSize + pbih->biClrUsed
* sizeof (RGBQUAD);
// Copy the BITMAPFILEHEADER into the .BMP file.
if (!WriteFile(hf, (LPVOID) &hdr, sizeof(BITMAPFILEHEADER),
(LPDWORD) &dwTmp, NULL))
{
Error("WriteFile");
}
// Copy the BITMAPINFOHEADER and RGBQUAD array into the file.
if (!WriteFile(hf, (LPVOID) pbih, sizeof(BITMAPINFOHEADER)
+ pbih->biClrUsed * sizeof (RGBQUAD),
(LPDWORD) &dwTmp, ( NULL))) {
Error("WriteFile"); }
// Copy the array of color indices into the .BMP file.
dwTotal = cb = pbih->biSizeImage;
hp = lpBits;
if (!WriteFile(hf, (LPSTR) hp, (int) cb, (LPDWORD) &dwTmp,NULL))
Error("WriteFile");
// Close the .BMP file.
if (!CloseHandle(hf))
Error("CloseHandle");
// Free memory.
GlobalFree((HGLOBAL)lpBits);
}
//错误显示
void ChdctobmpX::Error( TCHAR * pText )
{
::MessageBox( NULL, pText, TEXT("Error!"), MB_OK | MB_TASKMODAL | MB_SETFOREGROUND );
}
