FilenameFunctions

Description¶

This example gets a list of all files in a directory. It then extracts the file extension and filename from each string.

Question

If you have a question about this example, please use the VTK Discourse Forum

Code¶

FilenameFunctions.cxx

#include <string>
#include <vtkDirectory.h>
#include <vtkNew.h>
#include <vtksys/SystemTools.hxx>

int main(int argc, char* argv[])
{
  std::string directoryName;
  if (argc < 2)
  {
    directoryName = std::string(".");
  }
  else
  {
    directoryName = std::string(argv[1]);
  }

  vtkNew<vtkDirectory> directory;
  int opened = directory->Open(directoryName.c_str());

  if (!opened)
  {
    std::cout << "Invalid directory!" << std::endl;
    return EXIT_FAILURE;
  }

  int numberOfFiles = directory->GetNumberOfFiles();
  std::cout << "Number of files: " << numberOfFiles << std::endl;

  for (int i = 0; i < numberOfFiles; i++)
  {
    std::string fileString = directoryName;
    fileString += "/";
    fileString += directory->GetFile(i);

    std::string ext = vtksys::SystemTools::GetFilenameLastExtension(fileString);
    std::cout << fileString << " extension: " << ext << std::endl;

    std::string name =
        vtksys::SystemTools::GetFilenameWithoutLastExtension(fileString);
    std::cout << "name: " << name << std::endl;
  }

  return EXIT_SUCCESS;
}

CMakeLists.txt¶

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(FilenameFunctions)

find_package(VTK COMPONENTS 
  CommonCore
  CommonSystem
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "FilenameFunctions: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(FilenameFunctions MACOSX_BUNDLE FilenameFunctions.cxx )
  target_link_libraries(FilenameFunctions PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS FilenameFunctions
  MODULES ${VTK_LIBRARIES}
)

Download and Build FilenameFunctions¶

Click here to download FilenameFunctions and its CMakeLists.txt file. Once the tarball FilenameFunctions.tar has been downloaded and extracted,

cd FilenameFunctions/build

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./FilenameFunctions

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.