Qt读取图片有问题-应以二进制文件读取

Qt读取图片有问题-应以二进制文件读取

1. 通过二进制图区QImage

bool  GetImg(QImage &pix, QString &strFileName)
{
	QFile file(strFileName);
	char *m_pBuff = NULL;
	int m_nBuffSize;
	if (!file.open(QIODevice::ReadOnly))
	{
		QMessageBox::information(NULL, tr("Warning"), tr("File open fail."));
		return false;
	}
	int nSize = file.size();
	do
	{
		m_pBuff = new char[nSize + 1];
	} while (m_pBuff == NULL);

	QDataStream in(&file);
	//需要的有效长度为函数返回值，并非nSize
	m_nBuffSize = in.readRawData(m_pBuff, nSize);

	//读取失败则结束操作
	if (m_nBuffSize == -1)
	{
		return false;
	}

	//验证读取的数据，通过转化成图片显示出来
	if (!pix.loadFromData(reinterpret_cast<unsigned char*>(m_pBuff), m_nBuffSize))
	{
		return false;
	}
	return true;
}

2. 通过二进制读取QPixmap

bool  GetPix(QPixmap &pix,QString &strFileName)
{
	QFile file(strFileName);
	char *m_pBuff = NULL;
	int m_nBuffSize;
	if (!file.open(QIODevice::ReadOnly))
	{
		QMessageBox::information(NULL, tr("Warning"), tr("File open fail."));
		return false;
	}
	int nSize = file.size();
	do
	{
		m_pBuff = new char[nSize + 1];
	} while (m_pBuff == NULL);

	QDataStream in(&file);
	//需要的有效长度为函数返回值，并非nSize
	m_nBuffSize = in.readRawData(m_pBuff, nSize);

	//读取失败则结束操作
	if (m_nBuffSize == -1)
	{
		return false;
	}

	//验证读取的数据，通过转化成图片显示出来
	if (!pix.loadFromData(reinterpret_cast<unsigned char*>(m_pBuff), m_nBuffSize))
	{
		return false;
	}
	return true;
}

转载于:https://www.cnblogs.com/readlearn/p/10806386.html