C++学习日志41------path类:获取磁盘空间、路径分解、特殊运算符

• 一、获取磁盘空间
• 二、路径分解
• 三、特殊运算符

#include
#include

int main()
{
	using std::cout;
	using std::endl;
	namespace fs = std::filesystem;

	//定义路径对象
	fs::path p{ "C:\" };
	//展示磁盘的总大小和剩余大小
	cout << "C:total space:" << fs::space(p).capacity << endl;
	cout << "C:free space:" << fs::space(p).free << endl;

	std::cin.get();
	return 0;
}

结果如上图所示。

#include
#include
using std::cout;
using std::endl;
int main()
{
	namespace fs = std::filesystem;
	//定义路径p
	fs::path p{ R"(E:C_pphello.txt)" };
	//是否存在？根名？根路径？相对路径?
	if (p.empty())
	{
		cout << "Path" << p << "is empty." << endl;
	}
	if (!fs::exists(p))
	{
		cout << "Path" << p << "does not exist." << endl;
		std::exit(0);
	}

	cout << "root_name(): " << p.root_name() << "n"
		<< "root_path():" << p.root_path() << "n"
		<< "relative_path():" << p.relative_path() << "n";
	//父路径？文件名？文件名主干？拓展名？
	cout << "parent_path():" << p.parent_path() << "n"
		<< "filename():" << p.filename() << "n"
		<< "stem():" << p.stem() << "n"
		<< "extension():" << p.extension() << endl;

	std::cin.get();
}

结果如上图所示。

#include
#include
using std::cout;
using std::endl;
namespace fs = std::filesystem;
int main()
{
	fs::path p1{ R"(E:C_pp)" };
	fs::path p2{ R"(E:C_pp)" };
	fs::path p3{ " " };

	//append和/=  会自动添加/
	p1.append(R"(users)");
	p1 /= R"(cyd)";
	cout << p1 << endl;

	//concat和+=    不会自动添加/ 因此输出结果不合法
	p2.concat(R"(users)");
	p2 += R"(cyd)";

	cout << p2 << endl;

	//用运算符/拼凑一个新路径
	p3 = p3 / R"(C:temp)" / R"(users)" / R"(cyd)";

	cout << p3 << endl;
	std::cin.get();
}

结果如上图所示。