获取IE缓存中的文件（验证码图片）

[hnyztzh]

请教一个问题：
用windows API： FindFirstUrlCacheEntry、FindNextUrlCacheEntry 读取IE缓存，在IE缓存中获取不到网页的验证码图片文件， 我用httpwatch能抓取到验证码图片的URL。
不知道是什么原因获取不到验证码图片？ 请大牛帮忙指点如何解决获取不到验证码图片的问题!
或者说图片文件是以其他方式读取的？
代码如下：

HANDLE hCacheEnumHandle  = NULL;
	LPINTERNET_CACHE_ENTRY_INFO lpCacheEntry = NULL;
	DWORD dwTrySize = 0;    //initial buffer size
	DWORD dwEntrySize= 8192;  //initial buffer size

	// Delete index.dat if requested.
	// Be sure that index.dat is not locked.

	// Enable initial buffer size for cache entry structure. 
	lpCacheEntry = (LPINTERNET_CACHE_ENTRY_INFO) new char[dwEntrySize];
	lpCacheEntry->dwStructSize = dwEntrySize;
	dwTrySize = dwEntrySize;

	// URL search pattern (1st parameter)
	// options are:  NULL ("*.*"), "cookie:"  
	// or "visited:". 
	hCacheEnumHandle = FindFirstUrlCacheEntry(NULL /* in */ , 
		lpCacheEntry /* out */, 
		&dwTrySize /* in, out */);

	// First, obtain handle to internet cache
	// with FindFirstUrlCacheEntry 
	// for later use with FindNextUrlCacheEntry. 
	if (hCacheEnumHandle == NULL)
	{
		CString str;
		str.Format("error=%d\n",GetLastError());
		MessageBox(str,"1111111",MB_OKCANCEL);

		if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
		{
			delete [] lpCacheEntry;
			dwEntrySize = dwTrySize;
			lpCacheEntry = (LPINTERNET_CACHE_ENTRY_INFO) new char[dwEntrySize];
			lpCacheEntry->dwStructSize = dwEntrySize;

			hCacheEnumHandle = FindFirstUrlCacheEntry(NULL, lpCacheEntry , &dwTrySize);
		}
		else
		{
			goto ENDOF;
		}
	}


	if (hCacheEnumHandle)
	{
		TRACE("%s\n",lpCacheEntry->lpszSourceUrlName);
// 		if (strcmp(lpCacheEntry->lpszSourceUrlName,pszSrc) == 0)
// 		{
// 			CopyFile(lpCacheEntry->lpszLocalFileName,pszDst,FALSE);			
// 			goto ENDOF;
// 		}
	}

	// Next, use hCacheEnumHandle obtained
	// from the previous step to delete 
	// subsequent items of cache.
	while(TRUE) 
	{
		// Notice that return values of FindNextUrlCacheEntry (BOOL) and 
		// FindFirstUrlCacheEntry (HANDLE) are different.
		dwTrySize = dwEntrySize;
		BOOL bReturn = FindNextUrlCacheEntry(hCacheEnumHandle, lpCacheEntry, &dwTrySize);


		if (!bReturn)
		{
			CString str;
			str.Format("error=%d\n",GetLastError());
			MessageBox(str,"1111111",MB_OKCANCEL);


			if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
			{
				delete [] lpCacheEntry;
				dwEntrySize = dwTrySize;
				lpCacheEntry = (LPINTERNET_CACHE_ENTRY_INFO) new char[dwEntrySize];
				lpCacheEntry->dwStructSize = dwEntrySize;
				bReturn = FindNextUrlCacheEntry(hCacheEnumHandle, lpCacheEntry, &dwTrySize);
			}
			else
			{
				break;
			}
		}

		if (bReturn)
		{
			TRACE("%s\n",lpCacheEntry->lpszSourceUrlName);
// 			if (strcmp(lpCacheEntry->lpszSourceUrlName,pszSrc) == 0)
// 			{
// 				CopyFile(lpCacheEntry->lpszLocalFileName,pszDst,FALSE);
// 				break;
// 			}
		}

	} ;


ENDOF:

	if (lpCacheEntry) delete [] lpCacheEntry;
	if (hCacheEnumHandle) FindCloseUrlCache(hCacheEnumHandle);

[Yofoo]

直接用url下载就可以了 验证码图片一般设定不缓存