(C++) GetPath

 

 

GetPath is a file I/O std::string code snippet to get a filename's path.

 

• Download the Qt Creator project 'CppGetPath' (zip)

Technical facts

 

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• Console application

C++ standard:

• C++98

Compiler(s):

• G++ 4.9.2

Libraries used:

• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppGetPath/CppGetPath.pro

 

---

include(../../ConsoleApplication.pri) #Or use the code below # QT += core # QT += gui # greaterThan(QT_MAJOR_VERSION, 4): QT += widgets # CONFIG   += console # CONFIG   -= app_bundle # TEMPLATE = app # CONFIG(release, debug|release) { #   DEFINES += NDEBUG NTRACE_BILDERBIKKEL # } # QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ # unix { #   QMAKE_CXXFLAGS += -Werror # } include(../../Libraries/BoostAll.pri) SOURCES += main.cpp

 

 

 

 

 

./CppGetPath/main.cpp

 

---

#include <cassert> #include <string> #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #include <boost/filesystem.hpp> #include <boost/xpressive/xpressive.hpp> #pragma GCC diagnostic pop ///Returns the path of a filename ///From http://www.richelbilderbeek.nl/CppGetPath.htm const std::string GetPathStl(const std::string& filename) {   const int a = filename.rfind("\\",filename.size());   const int b = filename.rfind("/",filename.size());   const int i = std::max(a,b);   assert(i < static_cast<int>(filename.size()));   return filename.substr(0,i); } ///Returns the path of a filename //From http://www.richelbilderbeek.nl/CppGetPath.htm const std::string GetPathBoostFilesystem(const std::string& filename) {   return boost::filesystem::path(filename).parent_path().string(); } ///Returns the path of a filename ///From http://www.richelbilderbeek.nl/CppGetPath.htm const std::string GetPathBoostXpressive(const std::string& filename) {   const boost::xpressive::sregex rex     = boost::xpressive::sregex::compile(       "(.*)(\\\\|/)([A-Za-z\\._]*)" );   boost::xpressive::smatch what;   if( boost::xpressive::regex_match( filename, what, rex ) )   {     return what[1];   }   return ""; } #include <iostream> int main() {   #ifdef _WIN32   assert(GetPathBoostFilesystem("C:\\any_path\\any_file.cpp")=="C:\\any_path");   #else   assert(GetPathBoostFilesystem("/any_path/any_file.cpp")=="/any_path");   #endif   assert(GetPathBoostXpressive("C:\\any_path\\any_file.cpp")=="C:\\any_path");   assert(GetPathStl("C:\\any_path\\any_file.cpp")=="C:\\any_path");   assert(GetPathBoostXpressive("/any_path/any_file.cpp")=="/any_path");   assert(GetPathStl("/any_path/any_file.cpp")=="/any_path");   for (const auto f: { GetPathStl, GetPathBoostFilesystem, GetPathBoostXpressive} )   {     #ifdef _WIN32     assert(f("C:\\any_path\\any_file.cpp")=="C:\\any_path");     assert(f("any_path\\any_file.cpp")=="any_path");     #else     assert(f("/any_path/any_file.cpp")=="/any_path");     #endif   } }