c++ - 从导致AccessViolationException的线程访问文件缓冲区

Question

我有一些想要从线程中播放的声音。程序启动时，我将声音加载到内存中，然后使用Windows函数PlaySound播放声音。这可行，但是当我尝试从线程播放声音时，出现AccessViolationException，“尝试读取或写入 protected 内存”。

有没有一种方法可以将文件加载到char数组中，然后从单独的线程中读取文件？

这是我用来加载声音文件并播放它的代码。

// Code to load sound from file into char*.
    ifstream ifs(WaveSounds::sounds::StartupMusic, ios::binary | ios::ate);
	// The ios::ate flag sets the filestream
	// to the end position, so it's already
	// ata the end when we call 'tellg()'.
	if (&std::ios::ios_base::good)
	{		
		int length = ifs.tellg();
		ifs.seekg(0, ifs.beg);
		// Load into the Char * , 'n_StartMusic'.
		n_StartMusic = new char[length];
		ifs.read(n_StartMusic, length);
		ifs.close();
	}

// Plays sound from thread, causes AccessViolationException.
static void PlaySoundThread()
{		
	PlaySound((LPWSTR)WaveSounds::n_CurSound, NULL, SND_MEMORY | SND_ASYNC);
}

// Method that sets sound to play and starts thread.
void WaveSounds::Play_Sound(char* sound)
{		
	n_CurSound = sound;
	n_hmod = GetModuleHandle(0);
	Thread^ t = gcnew Thread(gcnew ThreadStart(PlaySoundThread));
	t->IsBackground = true;
	t->Start();	
}

Answer 1

如果char *声音通过wave.play_sound(＆c);传递到堆栈上的函数中。到线程启动时，c可能已被删除，因此m_nCurSound指向已清除的内存。

要解决此问题，请将m_nCurSound = sound更改为m_nCurSound = new char [255]; strcpy(声音，m_nCurSound);