Example of zooming an image using C in asp.net

Header file:

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#include <atlconv.h> #include <AtlBase.h> #include <tchar.h> #include "Gdiplus.h" #include <GdiPlusGraphics.h> using namespace Gdiplus; #pragma comment (lib, "Gdiplus.lib")

Cpp:

The code is as follows

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int Getencoderclsid (const wchar* format, clsid* pclsid) { UINT num = 0; Number of Image encoders UINT size = 0; Size of the image encoder array in bytes imagecodecinfo* pimagecodecinfo = NULL; Getimageencoderssize (&num, &size); if (size = = 0) return-1; Failure www.111cn.net Pimagecodecinfo = (imagecodecinfo*) (malloc (size)); if (Pimagecodecinfo = NULL) return-1; Failure Getimageencoders (num, size, pimagecodecinfo); for (UINT j = 0; j < num; ++j) { if (wcscmp (PIMAGECODECINFO[J). MimeType, format) = = 0) { *pclsid = Pimagecodecinfo[j]. Clsid; Free (pimagecodecinfo); Return J; Success } } Free (pimagecodecinfo); return-1; Failure } void Drawmainwindow (image* img,int w,int h) { HDC HDC = GetDC (AfxGetMainWnd ()->m_hwnd); if (HDC) { Graphics Graphics (HDC); Graphics. DrawImage (Img,w,h,img->getwidth (), Img->getheight ()); ReleaseDC (AfxGetMainWnd ()-&GT;M_HWND,HDC); } } void GetThumbnail (LPCSTR srcfile,lpcstr dstfile,int width,int height,bool) { Gdiplusstartupinput Gdiplusstartupinput; ULONG_PTR Gdiplustoken; Gdiplusstartup (&gdiplustoken,&gdiplusstartupinput,null); Uses_conversion; Image srcimage (a2w (srcfile)); Image *dstimage; int srcwidth = Srcimage.getwidth (); int srcheight = Srcimage.getheight (); if (constratio) { if (Width/srcwidth < height/srcheight) { Height = width * srcheight/srcwidth; } else { width = height * srcwidth/srcheight; } } Dstimage = Srcimage.getthumbnailimage (width,height); CLSID Imgclsid; Getencoderclsid (L "Image/jpeg", &imgclsid); Dstimage->save (a2w (dstfile), &imgclsid,null); Drawmainwindow (&srcimage,0,0); Drawmainwindow (Dstimage,0,srcimage.getheight () +10); Delete Dstimage; Dstimage = NULL; Gdiplusshutdown (Gdiplustoken); }

How to use:

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GetThumbnail ("Image.jpg", "cc.jpg", 200,80,true);