在richedit控件中插入动态GIF

这是CSDN的VC论坛上的一个老FAQ了。我在写自定义在RichEdit中插入对象的图标（http://www.blogcn.com/user3/jiangsheng/blog/1319738.html）这片文章的时候就是想用这个技术做动画GIF的，但是怎么判断一个内嵌在RichEdit的对象是GIF这个问题一直没有解决。好在QQ附带的一个控件支持动画GIF，可以插入这个对象来解决问题。

首先需要一个定时器来定时更新GIF。

public: System::Void OnLoad(System::Object^  sender, System::EventArgs^  e)
   {
   this->typingRichTextBox->RichTextShortcutsEnabled=false;
   this->timer1->Start();
   }

private: System::Void OnFormClosing(System::Object^  sender, System::Windows::Forms::FormClosingEventArgs^  e)
   {
    this->timer1->Stop();
    this->frameClosing=true;
   }

然后在定时器的处理函数里面通知GIF控件更新显示。

private: System::Void OnTimer1Elapsed(System::Object^  sender, System::Timers::ElapsedEventArgs^  e)
   {
    if(this->frameClosing==false)
    UnmanagedGifTriggerFrameChange(this->contentRichTextBox->Handle.ToInt32());
   }

最后的工作就是插入GIF了

private: System::Void smileToolStripMenuItem_Click(System::Object^  sender, System::EventArgs^  e)
   {
    insertemotion(sender,e,"c:\\Program Files\\Tencent\\QQ\\Face\\20.gif");
   }

private: System::Void insertemotion(System::Object^  sender, System::EventArgs^  e,String ^ gifPath)
   {
   System::Windows::Forms::RichTextBox^  ptypingRichTextBox=this->typingRichTextBox;
   stdcli::language::pin_ptr< wchar_t> wch = PtrToStringChars(gifPath);
   UnmanagedInsertGif(ptypingRichTextBox->Handle.ToInt32(),wch );
   }

为了偷懒起见关键的代码还是用Native C++来写，所以这些函数名全部以Unmanaged开头。

//unmanagedwin32.h
//混合托管和非托管编程的话，编译的时候不能使用/clr:safe和/clr:pure开关，
#pragma once
#pragma unmanaged//用这个开关来切换托管和非托管代码
extern void UnmanagedScrollToButton(int hwndRichEdit);
extern void UnmanagedInsertGif(int hwndRichEdit,wchar_t * pFilePath);
extern void UnmanagedGifTriggerFrameChange(int hwndRichEdit);
#pragma managed

//unmanagedwin32.cc

//使用了Windows 平台SDK
//必须要使用clr:oldSyntax来避免SDK头文件和C++/CLI语法的冲突
//而且在Visual C++ 2005 Express中要添加/d1PrivateNativeTypes 开关以避免混合LNK2022错误。
#define UNICODE
#define _UNICODE
#define  _WIN32_DCOM
#include "windows.h"
#include "Richedit.h"
#include "Richole.h"
#pragma comment( lib, "User32.lib" )
#include "UnmanagedWin32.h"
//纯用C编写自动化操作会死人的，幸好可以自动导入
#import "c:\\Program files\\tencent\\qq\\ImageOle.dll" named_guids
//移动光标到末尾然后调用System::Windows::Forms::RichTextBox的ScrollToCaret方法，需要拖动滚动条才可以看到最后一行之前的文字。老办法，API伺候。
void UnmanagedScrollToButton(int hwndRichEdit)
{
 HWND h=(HWND)hwndRichEdit;
 int line = SendMessage(h, EM_GETFIRSTVISIBLELINE, 0, 0);
 int linecount = SendMessage(h, EM_GETLINECOUNT, 0, 0);
 SendMessage(h, EM_LINESCROLL, 0, (linecount - line - 2));
}

下面的函数UnmanagedInsertGif(int hwndRichEdit,wchar_t * pFilePath)是插入一个ImageOle::GifAnimator对象，UnmanagedGifTriggerFrameChange(int hwndRichEdit)是枚举richedit中已经插入的对象，如果是ImageOle::GifAnimator对象，那么调用其TriggerFrameChange方法。

void UnmanagedInsertGif(int hwndRichEdit,wchar_t * pFilePath)<br />{<br /> HWND h=(HWND)hwndRichEdit;<br /> <br /> LPRICHEDITOLE lpRichEditOle=NULL;<br /> LPOLEOBJECT lpObject=NULL;<br /> LPSTORAGE lpStorage=NULL;<br /> LPOLECLIENTSITE lpClientSite=NULL;<br /> LPLOCKBYTES lpLockBytes = NULL;<br /><br /> REOBJECT reobject;<br /> ZeroMemory(&reobject, sizeof(REOBJECT));<br /> reobject.cbStruct = sizeof(REOBJECT); <br /><br /> HRESULT hr=S_OK;<br /> CLSID clsid=CLSID_NULL;<br /> do{<br /> ::SendMessage(h, EM_GETOLEINTERFACE, 0, (LPARAM)&lpRichEditOle);<br /> if(lpRichEditOle==NULL)break;<br /> hr= ::CreateILockBytesOnHGlobal(NULL, TRUE, &lpLockBytes);<br /> if (hr != S_OK||lpLockBytes==NULL) break;<br /> hr= ::StgCreateDocfileOnILockBytes(lpLockBytes,<br /> STGM_SHARE_EXCLUSIVE|STGM_CREATE|STGM_READWRITE, 0, &lpStorage);<br /> if (hr!= S_OK||lpStorage==NULL) break;<br /> hr=lpRichEditOle->GetClientSite(&lpClientSite);<br /> if (hr!= S_OK||lpClientSite==NULL) break;<br /> try<br /> {<br /> ImageOleLib::IGifAnimatorPtr lpAnimator;<br /> hr = lpAnimator.CreateInstance(ImageOleLib::CLSID_GifAnimator); <br /> if( FAILED(hr) ) _com_issue_error(hr);<br /> _bstr_t bstrPath(pFilePath);<br /> hr = lpAnimator->LoadFromFile(bstrPath);<br /> if( FAILED(hr) ) _com_issue_error(hr);<br /> hr = lpAnimator.QueryInterface(IID_IOleObject, (void**)&lpObject);<br /> if( FAILED(hr)||lpObject==NULL) _com_issue_error(hr);<br /> hr=OleSetContainedObject(lpObject, TRUE);<br /> if( FAILED(hr) ) _com_issue_error(hr);<br /> hr=lpObject->GetUserClassID(&clsid);<br /> if( FAILED(hr) ) _com_issue_error(hr);<br /> reobject.clsid = clsid;<br /> reobject.cp = REO_CP_SELECTION;<br /> reobject.dvaspect = DVASPECT_CONTENT;<br /> reobject.dwFlags = REO_BELOWBASELINE;<br /> reobject.dwUser = 0;<br /> reobject.poleobj = lpObject;<br /> reobject.polesite = lpClientSite;<br /> reobject.pstg = lpStorage;<br /> SIZEL sizel={0,0};<br /> reobject.sizel = sizel;<br /> hr=lpRichEditOle->InsertObject(&reobject);<br /> }<br /> catch( _com_error e )<br /> {<br /> LPCTSTR lpszErrMessage=e.ErrorMessage();<br /> }<br /><br /> }while(FALSE);<br /> if(lpLockBytes)<br /> lpObject->Release(); <br /> if(lpLockBytes)<br /> lpLockBytes->Release();<br /> if(lpClientSite)<br /> lpClientSite->Release();<br /> if(lpRichEditOle)<br /> lpRichEditOle->Release();<br />}<br />void UnmanagedGifTriggerFrameChange(int hwndRichEdit)<br />{<br /> HWND h=(HWND)hwndRichEdit;<br /> <br /> LPRICHEDITOLE lpRichEditOle=NULL;<br /> LPOLECLIENTSITE lpClientSite=NULL;<br /> LPOLECONTAINER lpContainer=NULL;<br /> LPENUMUNKNOWN lpEnumUnknown=NULL;<br /> HRESULT hr=S_OK; <br /> do{<br /> ::SendMessage(h, EM_GETOLEINTERFACE, 0, (LPARAM)&lpRichEditOle);<br /> if(lpRichEditOle==NULL)break;<br /> hr=lpRichEditOle->GetClientSite(&lpClientSite);<br /> if (hr!= S_OK||lpClientSite==NULL) break;<br /> hr=lpClientSite->GetContainer(&lpContainer);<br /> if (hr!= S_OK||lpClientSite==NULL) break;<br /> hr=lpContainer->EnumObjects(OLECONTF_EMBEDDINGS,&lpEnumUnknown);<br /> if (hr!= S_OK||lpEnumUnknown==NULL) break; <br /><br /> IUnknown* pUnk=NULL;<br /> ULONG uFetched=0;<br /> for (UINT i = 0; S_OK == lpEnumUnknown->Next(1, &pUnk, &uFetched); i++)<br /> {<br /> ImageOleLib::IGifAnimator* pAnimator=NULL;<br /> do{<br /> hr=pUnk->QueryInterface(__uuidof(ImageOleLib::IGifAnimator),(LPVOID*)&pAnimator);<br /> if (hr!= S_OK) break;<br /> try{<br /> ImageOleLib::IGifAnimatorPtr lpAnimator;<br /> lpAnimator.Attach(pAnimator,true);<br /> lpAnimator->TriggerFrameChange();<br /> }<br /> catch( _com_error e )<br /> {<br /> LPCTSTR lpszErrMessage=e.ErrorMessage();<br /> }<br /> }<br /> while(FALSE);<br /> pUnk->Release();<br /> if(pAnimator)<br /> pAnimator->Release();<br /> }<br /> }while(FALSE);<br /> if(lpEnumUnknown)<br /> lpEnumUnknown->Release();<br /> if(lpContainer)<br /> lpContainer->Release();<br /> if(lpRichEditOle)<br /> lpRichEditOle->Release();<br /> if(lpClientSite)<br /> lpClientSite->Release();<br />}

这两个函数里面的方法也可以用于插入其他类型控件，以及和插入的对象通讯。

使用windows 2000,QQ2004SP1,Visual C++ 2005 Express, Platform SDK (Windows 2003)编译测试。