C++文件路径处理2 - 路径拼接&路径解析
1. 关键词
关键词：
C++ 文件路径处理 路径拼接 获取父目录的路径 获取文件名 获取拓展名 跨平台
应用场景：
- 路径的拼接
- 路径的解析
2. filesystem.h
#pragma once
#include <string>
#include <iostream>
#include <cstdio>
#include "filetype.h"
namespace cutl
{
/**
* @brief The class for file path operations.
*
*/
class filepath
{
public:
/**
* @brief Construct a new filepath object
*
* @param path file path string
*/
filepath(const std::string &path);
/**
* @brief Construct a new filepath object by copy
*
* @param other other filepath object
*/
filepath(const filepath &other);
/**
* @brief Assign operator, assign a new filepath object by copy
*
* @param other other filepath object
* @return filepath& the reference of the current filepath object
*/
filepath &operator=(const filepath &other);
/**
* @brief Destroy the filepath object
*
*/
~filepath() = default;
public:
/**
* @brief Get the path separator of the current os platform.
*
* @return the path separator
*/
static char separator();
/**
* @brief Get the string of the filepath.
*
* @return the filepath
*/
std::string str() const;
/**
* @brief Join the current filepath with a new filename.
*
* @param filename the filename to be joined
* @return the new filepath object
*/
filepath join(const std::string &filename) const;
/**
* @brief Get the parent directory of the filepath.
*
* @return parent directory path
*/
std::string dirname() const;
/**
* @brief Get the filename or directory name of the filepath.
*
* @return filename or directory name
*/
std::string basename() const;
/**
* @brief Get the extension of the filepath.
*
* @return extension with dot
*/
std::string extension() const;
private:
std::string filepath_;
};
/**
* @brief Define the output stream operator for filepath object.
*
* @param os the std::ostream object
* @param fp the filepath object to be output
* @return std::ostream& the reference of the std::ostream object after outputing the filepath object.
*/
std::ostream &operator<<(std::ostream &os, const filepath &fp);
/**
* @brief Create a filepath object from a string.
*
* @param path file path string
* @return filepath object
*/
filepath path(const std::string &path);
} // namespace cutl
3. filepath.cpp
#include "filepath.h"
#include "inner/logger.h"
#include "inner/filesystem.h"
#include "strutil.h"
#include "sysutil.h"
namespace cutl
{
static constexpr char win_separator = '\\';
static constexpr char unix_separator = '/';
void fixpath(std::string &path)
{
if (win_separator == filepath::separator())
{
for (size_t i = 0; i < path.size(); i++)
{
if (path[i] == unix_separator)
{
path[i] = win_separator;
}
}
}
else if (unix_separator == filepath::separator())
{
for (size_t i = 0; i < path.size(); i++)
{
if (path[i] == win_separator)
{
path[i] = unix_separator;
}
}
}
else
{
// do nothing
}
while (path.empty() || path.back() == filepath::separator())
{
path.pop_back();
}
}
filepath::filepath(const std::string &path)
{
filepath_ = path;
fixpath(filepath_);
}
filepath::filepath(const filepath &other)
{
filepath_ = other.filepath_;
}
filepath &filepath::operator=(const filepath &other)
{
this->filepath_ = other.filepath_;
return *this;
}
char filepath::separator()
{
#if defined(_WIN32) || defined(__WIN32__)
return win_separator;
#else
return unix_separator;
#endif
}
std::string filepath::str() const
{
return filepath_;
}
filepath filepath::join(const std::string &filename) const
{
std::string path = filepath_ + separator() + filename;
return filepath(path);
}
std::string filepath::dirname() const
{
auto index = filepath_.find_last_of(separator());
if (index == std::string::npos)
{
return "";
}
return filepath_.substr(0, index);
}
std::string filepath::basename() const
{
auto index = filepath_.find_last_of(separator());
// auto len = filepath_.length() - index - 1;
if (index == std::string::npos)
{
return filepath_;
}
return filepath_.substr(index + 1);
}
std::string filepath::extension() const
{
auto pos = filepath_.find_last_of('.');
if (pos == std::string::npos)
{
return "";
}
return filepath_.substr(pos);
}
std::ostream &operator<<(std::ostream &os, const filepath &fp)
{
os << fp.str();
return os;
}
filepath path(const std::string &path)
{
return filepath(path);
}
} // namespace cutl
6. 测试代码
#include "common.hpp"
#include "fileutil.h"
void TestJoin()
{
PrintSubTitle("TestJoin");
auto path1 = cutl::path("/Users/spencer/workspace/common_util/src/usage_demo");
auto path2 = path1.join("filepath.hpp");
std::cout << "path1: " << path1 << std::endl;
std::cout << "path2: " << path2 << std::endl;
}
void TestDirnameBasename()
{
PrintSubTitle("TestDirnameBasename");
auto path1 = cutl::path("/Users/spencer/workspace/common_util/src/usage_demo/filepath.hpp");
std::cout << "path1: " << path1 << std::endl;
std::cout << "dirname: " << path1.dirname() << std::endl;
std::cout << "basename: " << path1.basename() << std::endl;
auto path2 = cutl::path("/Users/spencer/workspace/common_util/src/usage_demo");
std::cout << "path2: " << path2 << std::endl;
std::cout << "dirname: " << path2.dirname() << std::endl;
std::cout << "basename: " << path2.basename() << std::endl;
auto path3 = cutl::path("filepath.hpp");
std::cout << "path3: " << path3 << std::endl;
std::cout << "dirname: " << path3.dirname() << std::endl;
std::cout << "basename: " << path3.basename() << std::endl;
}
void TestExtenstion()
{
PrintSubTitle("TestExtenstion");
auto path1 = cutl::path("/Users/spencer/workspace/common_util/src/usage_demo/filepath.hpp");
std::cout << "path1: " << path1 << ", extension: " << path1.extension() << std::endl;
auto path2 = cutl::path("/Users/spencer/workspace/common_util/src/usage_demo/filepath");
std::cout << "path2: " << path2 << ", extension: " << path2.extension() << std::endl;
}
7. 运行结果
----------------------------------------------TestJoin----------------------------------------------
path1: /Users/spencer/workspace/common_util/src/usage_demo
path2: /Users/spencer/workspace/common_util/src/usage_demo/filepath.hpp
----------------------------------------TestDirnameBasename-----------------------------------------
path1: /Users/spencer/workspace/common_util/src/usage_demo/filepath.hpp
dirname: /Users/spencer/workspace/common_util/src/usage_demo
basename: filepath.hpp
path2: /Users/spencer/workspace/common_util/src/usage_demo
dirname: /Users/spencer/workspace/common_util/src
basename: usage_demo
path3: filepath.hpp
dirname:
basename: filepath.hpp
-------------------------------------------TestExtenstion-------------------------------------------
path1: /Users/spencer/workspace/common_util/src/usage_demo/filepath.hpp, extension: .hpp
path2: /Users/spencer/workspace/common_util/src/usage_demo/filepath, extension:
8. 源码地址
更多详细代码，请查看本人写的C++ 通用工具库: common_util, 本项目已开源，代码简洁，且有详细的文档和Demo。
