Change File Extension Context Menu

#include "stdafx.h"
#include "NewextDlg.h"
#include "Extmanager.h"

//
C_extmanager::C_extmanager()
{
	menubitmap.LoadBitmapW(MAKEINTRESOURCE(IDB_MENUBITMAP));
	if (menubitmap.IsNull()) throw EXTM_RES_ERROR;

	filecount=0;
	firstFileext.Empty();
	ctxFileext.Empty();

	v_fileList.clear();

}
//
C_extmanager::~C_extmanager()
{
	v_fileList.clear();
}
//
void C_extmanager::addFile(TCHAR *afl)
{
	CString fe;
	fe=afl;
	v_fileList.push_back(fe);//build file list

	filecount+=1;
	getfirstExt(afl);
}
//
void C_extmanager::getfirstExt(TCHAR *xtn)
{
	if (filecount==1)//just for first file	//filecount+=1; must be called before this
	{
	splitter.Split(xtn);//split path for ext	//check for empty ext!!!
	ctxFileext=firstFileext=splitter.ext_nodot;
	ctxFileext.MakeUpper();
	}
}
//
void C_extmanager::processFiles()
{
	nextdlg.newext=firstFileext;
}
//
void C_extmanager::changeExtensions()
{
	if (nextdlg.DoModal()!=IDOK) return;

	//now change extensions
	if (filecount>0)
	{
		for ( v_fileListiter=v_fileList.begin(); v_fileListiter<v_fileList.end(); v_fileListiter++)
		{if (!changeExt(*v_fileListiter, nextdlg.newext)) break;}
	}
}
//
bool C_extmanager::changeExt(CString &fname,CString &newext)
{
try {
	splitter.Split(fname);
	splitter.ext_nodot.MakeLower();

	CString toname=newext;//reusing toname
	toname.MakeLower();

	if (splitter.ext_nodot==toname) return true;//case-insensitive compare

	toname.Empty();//reusing toname

	SHFILEOPSTRUCT lpFileOp;
	memset(&lpFileOp,0,sizeof(lpFileOp));

	lpFileOp.hwnd=NULL;
	lpFileOp.fFlags=FOF_ALLOWUNDO;
	lpFileOp.wFunc=FO_RENAME;

	fname+='\0';//add buffer-terminating null to old name
	lpFileOp.pFrom=fname;

	toname=splitter.drive+splitter.dir+splitter.filename+_T(".")+newext;
	lpFileOp.pTo=toname;
	
	if (0!=SHFileOperation(&lpFileOp)) {/*MSGBOX0("SHFileOperation failed");*/return false;}
} catch (...) {return false;}
return true;
}