C++文本读写记录

使用C++常规的读写方式，即std::ifstream和std::ofstream

记录

pcl::PointCloud<pcl::PointXYZRGB>::Ptr PointCloudGUI::readASCPoint(std::string path)
{
    
    
	std::ifstream ifs(path, std::ios::in);
	if (!ifs.is_open())
	{
    
    
		std::cout << "文件不存在" << std::endl;
		ifs.close();
		return NULL;
	}

	char ch;
	ifs >> ch;
	if (ifs.eof())
	{
    
    
		std::cout << "文件为空" << std::endl;
		ifs.close();
		return NULL;
	}
	ifs.putback(ch);

	pcl::PointCloud<pcl::PointXYZ>::Ptr basic_cloud_ptr(new pcl::PointCloud<pcl::PointXYZ>);
	std::string data_;
	int i = 0;
	int num = 0;
	std::vector<pcl::PointXYZ> v;
	v.push_back(pcl::PointXYZ(0, 0, 0));
	while (ifs >> data_)
	{
    
    
		i++;
		if (i % 3 == 1)
			v[num].x = std::atof(data_.c_str());
		if (i % 3 == 2)
			v[num].y = std::atof(data_.c_str());
		if (i % 3 == 0)
		{
    
    
			v[num].z = std::atof(data_.c_str());
			v.push_back(pcl::PointXYZ(0, 0, 0));
			basic_cloud_ptr->points.push_back(v[num]);
			num++;
		}


	}
	v.pop_back();

	
	ifs.close();
	pcl::PointCloud<pcl::PointXYZRGB>::Ptr m_cloud(new pcl::PointCloud<pcl::PointXYZRGB>);
	pcl::copyPointCloud(*basic_cloud_ptr, *m_cloud);    // PointXYZ转化为PointXYZRGB
	return m_cloud;
}```