看了下sqlITE3的操作类，对于blob的字段存/取操作已经会用了。

但是只能一次性的读取文件长度，然后分配内存。对于分批次写入，我现在还没有弄明白，需要进一步的学习。

写在这里记录一下吧。

        Cppsqlite3DB db;
	LPCSTR pstrFileName ="d:\\test.s3db";
	try
	{ 
		db.open(pstrFileName); 

		unsigned char* bin ; 
		Cppsqlite3Binary  blob;

 
		HANDLE hFile = CreateFile("c:\\test.bmp",GENERIC_READ,FILE_SHARE_READ,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);

		DWORD dwFileSize=0;
		dwFileSize =GetFileSize(hFile,&dwFileSize);
		bin = new unsigned char[dwFileSize];//一次性分配内存 ，好郁闷啊。
		//写入数据库	
		DWORD dwRead = 0 ;
		DWORD dwSize = dwFileSize;
		ReadFile(hFile,bin,dwSize,&dwRead,0);
		blob.setBinary(bin,dwSize);
		Cppsqlite3Buffer bufsql;
		bufsql.format("insert into bindata values ('testing',%Q);",blob.getEncoded());
		db.execDML(bufsql);	 

		CloseHandle(hFile);
		delete bin; 
		//读取blob字段，并创建生成新的文件	
		hFile = CreateFile("c:\\TEST2.bmp",GENERIC_WRITE,OPEN_ALWAYS,0);
		Cppsqlite3Query q ;
		q = db.execQuery("select data from bindata where desc = 'testing';");
		
		//读到内存中	
		if (!q.eof())
		{
			blob.setEncoded((unsigned char*)q.fieldValue("data")); 
		}

		const unsigned char* pbin = blob.getBinary();

		DWORD dwWrite;
		WriteFile(hFile,pbin,blob.getBinaryLength(),&dwWrite,0);//写入文件 
		CloseHandle(hFile);

	}
	catch(Cppsqlite3Exception &e)
	{
		m_list.AddString(e.errorMessage());
	}