C++ || How To Get The File Name & File Extension From A Path Using C++

December 05, 2020 admin No comments

The following is a module with functions which demonstrates how to parse a file name and file extension from a path using C++.

1. Get File Name

The example below demonstrates the use of ‘Utils::getFileName‘ to parse and get the file name from a path.



		
		
			1. Get File Name
			
C++
			
			// Get File Name

// Declare path
std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";

// Get the filename
auto fileName = Utils::getFileName(path);

std::cout << "Path: " + path + ", File Name: " + fileName;

// expected output:
/*
    Path: C:\Users\Name\Desktop\20171216_155433.jpg, File Name: 20171216_155433.jpg
*/
			
				
					
				
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						// Get File Name
 
// Declare path
std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";
 
// Get the filename
auto fileName = Utils::getFileName(path);
 
std::cout << "Path: " + path + ", File Name: " + fileName;
 
// expected output:
/*
    Path: C:\Users\Name\Desktop\20171216_155433.jpg, File Name: 20171216_155433.jpg
*/

2. Get File Name Extension

The example below demonstrates the use of ‘Utils::getFileExtension‘ to parse and get the file extension from a path.



		
		
			2. Get File Name Extension
			
C++
			
			// Get File Name Extension

// Declare path
std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";

// Get the file extension
auto extension = Utils::getFileExtension(path);

std::cout << "Path: " + path + ", File Extension: " + extension;

// expected output:
/*
    Path: C:\Users\Name\Desktop\20171216_155433.jpg, File Extension: jpg
*/
			
				
					
				
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						// Get File Name Extension
 
// Declare path
std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";
 
// Get the file extension
auto extension = Utils::getFileExtension(path);
 
std::cout << "Path: " + path + ", File Extension: " + extension;
 
// expected output:
/*
    Path: C:\Users\Name\Desktop\20171216_155433.jpg, File Extension: jpg
*/

3. Utils Namespace

The following is the Utils Namespace. Include this in your project to start using!



		
		
			Utils Namespace
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Dec 5, 2020
//    Taken From: http://programmingnotes.org/
//    File:  Utils.h
//    Description: Handles general utility functions
// ============================================================================
#pragma once 
#include <string>
#include <algorithm>
#include <cctype>

namespace Utils {
    /**
    * FUNCTION: getFileName
    * USE: Returns the file name from a given path
    * @param path: The path of the file
    * @return: The file name from the given path
    */
    std::string getFileName(const std::string& path) {
        auto fileNameStart = path.find_last_of("/\\");
        auto fileName = fileNameStart == std::string::npos ? path : path.substr(fileNameStart + 1);
        return fileName;
    }

    /**
    * FUNCTION: getFileExtension
    * USE: Returns the file extension from a given path
    * @param path: The path of the file
    * @return: The file extension from the given path
    */
    std::string getFileExtension(const std::string& path) {
        auto fileName = getFileName(path);
        auto extStart = fileName.find_last_of('.');
        auto ext = extStart == std::string::npos ? "" : fileName.substr(extStart + 1);
        std::transform(ext.begin(), ext.end(), ext.begin(), [](unsigned char c) { return std::tolower(c); });
        return ext;
    }
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Dec 5, 2020
//    Taken From: http://programmingnotes.org/
//    File:  Utils.h
//    Description: Handles general utility functions
// ============================================================================
#pragma once 
#include <string>
#include <algorithm>
#include <cctype>
 
namespace Utils {
    /**
    * FUNCTION: getFileName
    * USE: Returns the file name from a given path
    * @param path: The path of the file
    * @return: The file name from the given path
    */
    std::string getFileName(const std::string& path) {
        auto fileNameStart = path.find_last_of("/\\");
        auto fileName = fileNameStart == std::string::npos ? path : path.substr(fileNameStart + 1);
        return fileName;
    }
 
    /**
    * FUNCTION: getFileExtension
    * USE: Returns the file extension from a given path
    * @param path: The path of the file
    * @return: The file extension from the given path
    */
    std::string getFileExtension(const std::string& path) {
        auto fileName = getFileName(path);
        auto extStart = fileName.find_last_of('.');
        auto ext = extStart == std::string::npos ? "" : fileName.substr(extStart + 1);
        std::transform(ext.begin(), ext.end(), ext.begin(), [](unsigned char c) { return std::tolower(c); });
        return ext;
    }
}// http://programmingnotes.org/

4. More Examples

Below are more examples demonstrating the use of the ‘Utils‘ Namespace. Don’t forget to include the module when running the examples!



		
		
			More Examples
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Dec 5, 2020
//    Taken From: http://programmingnotes.org/
//    File:  program.cpp
//    Description: The following demonstrates the use of the Utils Namespace.
// ============================================================================
#include <iostream>
#include <string>
#include <exception>
#include "Utils.h"

void display(const std::string& message);

int main() {
    try {
        // Declare path
        std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";
        
        // Get the filename
        auto fileName = Utils::getFileName(path);

        display("Path: " + path + ", File Name: " + fileName);

        // Get the file extension
        auto extension = Utils::getFileExtension(path);

        display("Path: " + path + ", File Extension: " + extension);

    } catch (std::exception& e) {
        display("\nAn error occurred: " + std::string(e.what()));
    }

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

void display(const std::string& message) {
    std::cout << message << std::endl;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Dec 5, 2020
//    Taken From: http://programmingnotes.org/
//    File:  program.cpp
//    Description: The following demonstrates the use of the Utils Namespace.
// ============================================================================
#include <iostream>
#include <string>
#include <exception>
#include "Utils.h"
 
void display(const std::string& message);
 
int main() {
    try {
        // Declare path
        std::string path = "C:\\Users\\Name\\Desktop\\20171216_155433.jpg";
        
        // Get the filename
        auto fileName = Utils::getFileName(path);
 
        display("Path: " + path + ", File Name: " + fileName);
 
        // Get the file extension
        auto extension = Utils::getFileExtension(path);
 
        display("Path: " + path + ", File Extension: " + extension);
 
    } catch (std::exception& e) {
        display("\nAn error occurred: " + std::string(e.what()));
    }
 
    std::cin.get();
    return 0;
}
 
void display(const std::string& message) {
    std::cout << message << std::endl;
}// http://programmingnotes.org/