当获得了DC的句柄，如何把DC上的区域保存到一个位图文件中？

[AnyStayIsJk]

当获得了DC的句柄，如何把DC上的区域保存到一个位图文件中？谢谢

[lambochan]

晕,应为:
BitBlt( hMemDC, 0, 0, bi.biWidth, bi.biHeight, saveDC, rc.left, rc.top, SRCCOPY );

才对.

[lambochan]

[Quote=引用 8 楼 anystayisjk 的回复:]
请用SDK的方式，别用MFC，我的整个程序是SDK的。谢谢了
[/Quote]

CFile file( lpszFileName, CFile::modeCreate|CFile::modeWrite );
file.Write( &bf, sizeof( BITMAPFILEHEADER ) );
file.Write( &bi, sizeof( BITMAPINFOHEADER ) );
file.WriteHuge( lpBits, bi.biSizeImage );
把这几句替换成writefile..
DWORD dwWrite;
HANDLE fh = CreateFile( lpszFileName, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL );
WriteFile( fh, ( LPBYTE )&bf, sizeof( BITMAPFILEHEADER ), &dwWrite, NULL );
WriteFile( fh, ( LPBYTE )&bi, sizeof( BITMAPINFOHEADER ), &dwWrite, NULL );
WriteFile( fh, ( LPBYTE )lpBits, bi.biSizeImage, &dwWrite, NULL );

汗...

[AnyStayIsJk]

报这两个错误

1>c:\documents and settings\cx\桌面\textusenglish\textusenglish\textusenglish\textusenglish.cpp(25) : error C3861: “WIDTHBYTES”: 找不到标识符
1>c:\documents and settings\cx\桌面\textusenglish\textusenglish\textusenglish\textusenglish.cpp(38) : error C2660: “SelectObject”: 函数不接受 1 个参数

[lambochan]

2: HBITMAP hOldBmp = ( HBITMAP )SelectObject( hMemDC, hBitmap );
1: #define WIDTHBYTES(w,b) ((((w)*(b)+31)/32)*4)

[lambochan]

#define WIDTHBYTES(w,b) ((((w)*(b)+31)/32)*4)
BOOL Save( LPCTSTR lpszFileName, HDC saveDC, RECT rc ) 
{ 
    BITMAPFILEHEADER bf = { 0 }; 
    BITMAPINFOHEADER bi = { 0 }; 
    HDC hMemDC; 
    HBITMAP hBitmap; 
    LPBYTE lpBits; 

    bi.biSize = sizeof( BITMAPINFOHEADER ); 
    bi.biBitCount = 24; // 保存为true color 
    bi.biWidth = rc.right - rc.left; 
    bi.biHeight = rc.bottom - rc.top; 
    bi.biPlanes = 1; 
    bi.biCompression = BI_RGB; 
    bi.biSizeImage = WIDTHBYTES( bi.biWidth, bi.biBitCount ) * bi.biHeight; 

    HDC hdc = GetDC( NULL ); 
    if( !hdc ) 
        return FALSE; 
    hBitmap = CreateDIBSection( hdc, ( CONST BITMAPINFO * )&bi, DIB_RGB_COLORS, 
                        ( VOID ** )&lpBits, NULL, 0 ); 
    if( !hBitmap ){ 
        ReleaseDC( NULL, hdc ); 
        return FALSE; 
    } 

    hMemDC = CreateCompatibleDC( hdc ); 
    HBITMAP hOldBmp = ( HBITMAP )SelectObject( hMemDC, hBitmap ); 
    BitBlt( hMemDC, 0, 0, bi.biWidth, bi.biHeight, saveDC, 0, 0, SRCCOPY ); 
    SelectObject( hMemDC, hOldBmp ); 
    ReleaseDC( NULL, hdc ); 
    DeleteDC( hMemDC ); 

    bf.bfType = 0x4d42; 
    bf.bfSize = sizeof( BITMAPFILEHEADER ) + sizeof( BITMAPINFOHEADER ) 
                + bi.biSizeImage; 
    bf.bfOffBits = sizeof( BITMAPFILEHEADER ) + sizeof( BITMAPINFOHEADER ); 

    DWORD dwWrite; 
    HANDLE fh = CreateFile( lpszFileName, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, 
                        FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL ); 
    WriteFile( fh, ( LPBYTE )&bf, sizeof( BITMAPFILEHEADER ), &dwWrite, NULL ); 
    WriteFile( fh, ( LPBYTE )&bi, sizeof( BITMAPINFOHEADER ), &dwWrite, NULL ); 
    WriteFile( fh, ( LPBYTE )lpBits, bi.biSizeImage, &dwWrite, NULL ); 


    DeleteObject( hBitmap ); 
    return TRUE; 
}

还有没?估计这个没有了.

因为是随手写的.哈哈~

[AnyStayIsJk]

编译通过了，可是如何把LPRECT t转换成RECT t后并赋给Save((LPCTSTR)"c:\\jk.bmp",hdc,t);呢？

[AnyStayIsJk]

error C2664: “GetWindowRect”: 不能将参数 1 从“HDC”转换为“HWND”

[lambochan]

倒..
BitBlt( hMemDC, 0, 0, bi.biWidth, bi.biHeight, saveDC, 0, 0, SRCCOPY );
这个又不记得改回:
BitBlt( hMemDC, 0, 0, bi.biWidth, bi.biHeight, saveDC, rc.left, rc.top, SRCCOPY );

-_-"..

good luck~不搞了..哈哈

[AnyStayIsJk]

我位图这块比较差，谢谢了，就差这个了，如何把LPRECT t转换成RECT t后并赋给Save((LPCTSTR)"c:\\jk.bmp",hdc,t);呢？谢谢

[lyserver]

#include "stdafx.h"
#include <ocidl.h>
#include <olectl.h>
// ////////////////////////////////////////
// 函数名称：DC2File
// 函数功能：将指定DC中的位图保存为BMP文件
// ////////////////////////////////////////
BOOL DC2File(HDC hDC,LPCSTR szFileName,UINT nLeft=0,UINT nTop=0,UINT nWidth=0,UINT nHeight=0)
{
HDC hMemDC;
BITMAP bmp;
HBITMAP hSrcBmp,hMemBmp,hOldBmp;
BOOL retVal=FALSE;

hSrcBmp=(HBITMAP)GetCurrentObject(hDC,OBJ_BITMAP);
if(hSrcBmp==NULL)return FALSE;

GetObject(hSrcBmp,sizeof(BITMAP),&bmp);
if(nWidth>(UINT)bmp.bmWidth)nWidth=(UINT)bmp.bmWidth;
if(nHeight>(UINT)bmp.bmHeight)nHeight=(UINT)bmp.bmHeight;
if( nWidth<nLeft || nHeight<nTop)return 0;

hMemDC = CreateCompatibleDC(hDC);
hMemBmp = CreateCompatibleBitmap(hDC,(nWidth-nLeft),(nHeight-nTop));
hOldBmp = (HBITMAP)SelectObject(hMemDC,hMemBmp);
BitBlt(hMemDC,nLeft,nTop,(nWidth-nLeft),(nHeight-nTop),hDC,nLeft,nTop,SRCCOPY);

PICTDESC ps;
IPicture* pIPic=NULL;
ps.cbSizeofstruct = sizeof(PICTDESC);
ps.picType = PICTYPE_BITMAP;
ps.bmp.hbitmap = hMemBmp;
ps.bmp.hpal = NULL;
if(OleCreatePictureIndirect(&ps,IID_IPicture,TRUE,(LPVOID*)&pIPic)==ERROR_SUCCESS)
{
LONG lSize = 0;
IStream* pIStm = NULL;
CreateStreamOnHGlobal(NULL,TRUE,&pIStm);
if(pIPic->SaveAsFile(pIStm,TRUE,&lSize) == ERROR_SUCCESS)
{
LARGE_INTEGER li;
li.HighPart = 0;
li.LowPart = 0;
ULARGE_INTEGER uli;
uli.HighPart = 0;
uli.LowPart = 0;
pIStm->Seek(li, STREAM_SEEK_SET, &uli);

char buffer[1024];
HANDLE hFile = CreateFile(szFileName, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_HIDDEN, NULL);
DWORD dwRead = 1,dwWrite=0;
while(dwRead>0)
{
pIStm->Read(buffer, 1024, &dwRead);
if(dwRead > 0)WriteFile(hFile, buffer, dwRead, &dwWrite, NULL);
}
CloseHandle(hFile);
retVal=TRUE;
}
pIPic->Release();
pIStm->Release();
}
DeleteObject(SelectObject(hMemDC,hOldBmp));
DeleteDC(hMemDC);
return retVal;
}

[lambochan]

[Quote=引用 14 楼 anystayisjk 的回复:]
编译通过了，可是如何把LPRECT t转换成RECT t后并赋给Save((LPCTSTR)"c:\\jk.bmp",hdc,t);呢？
[/Quote]

Save((LPCTSTR)"c:\\jk.bmp",hdc,*t);

HWND是你的窗口的句柄,而不是DC句柄.
GetWindowRect()需要的是程序窗口句柄吧.
GetClientRect()是客户区窗口句柄.

[lyserver]

调用代码:

int APIENTRY WinMain(HINSTANCE hInstance,
    HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nCmdShow)
{
    HDC hDesktopDC=GetDC(NULL);
    DC2File(hDesktopDC,"c:\\temp.bmp",0,0,800,500);
	ReleaseDC(NULL,hDesktopDC);
     MessageBox(NULL,"保存完毕！","",MB_OK);
    return 0;
}

[AnyStayIsJk]

那如何获得程序的窗口的句柄呢？我的代码运行于HOOK了的ExtTextOutA函数的内部，若方便请留下QQ，我的291187020，我是做逆向的。。。。。。。

[AnyStayIsJk]

我用 CreateFileA创建位图时返回INVALID_HANDLE_VALUE，请问是什么原因呀？？谢谢了

[dby99]

ReleaseDC(NULL, hMemDC );
报编译错误，error C2660: 'ReleaseDC' : function does not take 2 parameters
请问怎么回事？

[AnyStayIsJk]

参数个数问题

[dby99]

我看到有些代码上没有用ReleaseDC(NULL, hMemDC );这一句，会不会产生内存泄露啊？

[sevenzhy]

[Quote=引用 25 楼 dby99 的回复:]
我看到有些代码上没有用ReleaseDC(NULL, hMemDC );这一句，会不会产生内存泄露啊？
[/Quote]

没有GetDC()就不需要ReleaseDC()，成对使用.

[nokianasty]

mark

[wj120202]

学习了！