Encodeur/Décodeur Base64

// Codage/Décodage Base64 en JavaScript
function encodeToBase64(text) {
  return btoa(text);
}

function decodeFromBase64(base64String) {
  try {
    return atob(base64String);
  } catch (e) {
    throw new Error("Chaîne Base64 invalide");
  }
}

// Exemple d'utilisation
const originalText = "Hello, World!";
const encoded = encodeToBase64(originalText);
console.log("Encodé :", encoded);  // SGVsbG8sIFdvcmxkIQ==

try {
  const decoded = decodeFromBase64(encoded);
  console.log("Décodé :", decoded);  // Hello, World!
} catch (error) {
  console.error(error.message);
}

# Codage/Décodage Base64 en Python
import base64

def encode_to_base64(text):
    # Convertir la chaîne en octets puis encoder
    text_bytes = text.encode('utf-8')
    base64_bytes = base64.b64encode(text_bytes)
    return base64_bytes.decode('utf-8')

def decode_from_base64(base64_string):
    try:
        # Convertir la chaîne base64 en octets puis décoder
        base64_bytes = base64_string.encode('utf-8')
        text_bytes = base64.b64decode(base64_bytes)
        return text_bytes.decode('utf-8')
    except Exception as e:
        raise ValueError(f"Chaîne Base64 invalide : {e}")

# Exemple d'utilisation
original_text = "Hello, World!"
encoded = encode_to_base64(original_text)
print(f"Encodé : {encoded}")  # SGVsbG8sIFdvcmxkIQ==

try:
    decoded = decode_from_base64(encoded)
    print(f"Décodé : {decoded}")  # Hello, World!
except ValueError as e:
    print(e)

// Codage/Décodage Base64 en Java
import java.util.Base64;
import java.nio.charset.StandardCharsets;

public class Base64Example {
    public static String encodeToBase64(String text) {
        byte[] textBytes = text.getBytes(StandardCharsets.UTF_8);
        byte[] encodedBytes = Base64.getEncoder().encode(textBytes);
        return new String(encodedBytes, StandardCharsets.UTF_8);
    }
    
    public static String decodeFromBase64(String base64String) {
        try {
            byte[] base64Bytes = base64String.getBytes(StandardCharsets.UTF_8);
            byte[] decodedBytes = Base64.getDecoder().decode(base64Bytes);
            return new String(decodedBytes, StandardCharsets.UTF_8);
        } catch (IllegalArgumentException e) {
            throw new IllegalArgumentException("Chaîne Base64 invalide : " + e.getMessage());
        }
    }
    
    public static void main(String[] args) {
        String originalText = "Hello, World!";
        String encoded = encodeToBase64(originalText);
        System.out.println("Encodé : " + encoded);  // SGVsbG8sIFdvcmxkIQ==
        
        try {
            String decoded = decodeFromBase64(encoded);
            System.out.println("Décodé : " + decoded);  // Hello, World!
        } catch (IllegalArgumentException e) {
            System.err.println(e.getMessage());
        }
    }
}

<?php
// Codage/Décodage Base64 en PHP
function encodeToBase64($text) {
    return base64_encode($text);
}

function decodeFromBase64($base64String) {
    $decoded = base64_decode($base64String, true);
    if ($decoded === false) {
        throw new Exception("Chaîne Base64 invalide");
    }
    return $decoded;
}

// Exemple d'utilisation
$originalText = "Hello, World!";
$encoded = encodeToBase64($originalText);
echo "Encodé : " . $encoded . "\n";  // SGVsbG8sIFdvcmxkIQ==

try {
    $decoded = decodeFromBase64($encoded);
    echo "Décodé : " . $decoded . "\n";  // Hello, World!
} catch (Exception $e) {
    echo "Erreur : " . $e->getMessage() . "\n";
}
?>

// Codage/Décodage Base64 en C#
using System;
using System.Text;

class Base64Example
{
    public static string EncodeToBase64(string text)
    {
        byte[] textBytes = Encoding.UTF8.GetBytes(text);
        return Convert.ToBase64String(textBytes);
    }
    
    public static string DecodeFromBase64(string base64String)
    {
        try
        {
            byte[] base64Bytes = Convert.FromBase64String(base64String);
            return Encoding.UTF8.GetString(base64Bytes);
        }
        catch (FormatException)
        {
            throw new FormatException("Chaîne Base64 invalide");
        }
    }
    
    static void Main()
    {
        string originalText = "Hello, World!";
        string encoded = EncodeToBase64(originalText);
        Console.WriteLine($"Encodé : {encoded}");  // SGVsbG8sIFdvcmxkIQ==
        
        try
        {
            string decoded = DecodeFromBase64(encoded);
            Console.WriteLine($"Décodé : {decoded}");  // Hello, World!
        }
        catch (FormatException e)
        {
            Console.WriteLine($"Erreur : {e.Message}");
        }
    }
}

# Codage/Décodage Base64 en Ruby
require 'base64'

def encode_to_base64(text)
  Base64.strict_encode64(text)
end

def decode_from_base64(base64_string)
  begin
    Base64.strict_decode64(base64_string)
  rescue ArgumentError => e
    raise "Chaîne Base64 invalide : #{e.message}"
  end
end

# Exemple d'utilisation
original_text = "Hello, World!"
encoded = encode_to_base64(original_text)
puts "Encodé : #{encoded}"  # SGVsbG8sIFdvcmxkIQ==

begin
  decoded = decode_from_base64(encoded)
  puts "Décodé : #{decoded}"  # Hello, World!
rescue StandardError => e
  puts "Erreur : #{e.message}"
end

// Codage/Décodage Base64 en Go
package main

import (
    "encoding/base64"
    "fmt"
)

func encodeToBase64(text string) string {
    return base64.StdEncoding.EncodeToString([]byte(text))
}

func decodeFromBase64(base64String string) (string, error) {
    bytes, err := base64.StdEncoding.DecodeString(base64String)
    if err != nil {
        return "", fmt.Errorf("chaîne Base64 invalide : %v", err)
    }
    return string(bytes), nil
}

func main() {
    originalText := "Hello, World!"
    encoded := encodeToBase64(originalText)
    fmt.Println("Encodé :", encoded)  // SGVsbG8sIFdvcmxkIQ==
    
    decoded, err := decodeFromBase64(encoded)
    if err != nil {
        fmt.Println("Erreur :", err)
    } else {
        fmt.Println("Décodé :", decoded)  // Hello, World!
    }
}

// Codage/Décodage Base64 en Swift
import Foundation

func encodeToBase64(_ text: String) -> String? {
    if let data = text.data(using: .utf8) {
        return data.base64EncodedString()
    }
    return nil
}

func decodeFromBase64(_ base64String: String) -> String? {
    if let data = Data(base64Encoded: base64String) {
        return String(data: data, encoding: .utf8)
    }
    return nil
}

// Exemple d'utilisation
let originalText = "Hello, World!"
if let encoded = encodeToBase64(originalText) {
    print("Encodé : \(encoded)")  // SGVsbG8sIFdvcmxkIQ==
    
    if let decoded = decodeFromBase64(encoded) {
        print("Décodé : \(decoded)")  // Hello, World!
    } else {
        print("Erreur : Impossible de décoder la chaîne Base64")
    }
} else {
    print("Erreur : Impossible d'encoder le texte")
}

' Codage/Décodage Base64 en VBA Excel
' Remarque : Cela nécessite une référence à Microsoft XML, v6.0
Function EncodeToBase64(text As String) As String
    Dim xmlObj As Object
    Set xmlObj = CreateObject("MSXML2.DOMDocument")
    
    Dim xmlNode As Object
    Set xmlNode = xmlObj.createElement("b64")
    
    xmlNode.DataType = "bin.base64"
    xmlNode.nodeTypedValue = StrConv(text, vbFromUnicode)
    
    EncodeToBase64 = xmlNode.text
    
    Set xmlNode = Nothing
    Set xmlObj = Nothing
End Function

Function DecodeFromBase64(base64String As String) As String
    On Error GoTo ErrorHandler
    
    Dim xmlObj As Object
    Set xmlObj = CreateObject("MSXML2.DOMDocument")
    
    Dim xmlNode As Object
    Set xmlNode = xmlObj.createElement("b64")
    
    xmlNode.DataType = "bin.base64"
    xmlNode.text = base64String
    
    DecodeFromBase64 = StrConv(xmlNode.nodeTypedValue, vbUnicode)
    
    Set xmlNode = Nothing
    Set xmlObj = Nothing
    Exit Function
    
ErrorHandler:
    DecodeFromBase64 = "Erreur : Chaîne Base64 invalide"
End Function

' Utilisation dans une feuille de calcul :
' =EncodeToBase64("Hello, World!")
' =DecodeFromBase64("SGVsbG8sIFdvcmxkIQ==")

# Codage/Décodage Base64 en R
# Nécessite le package 'base64enc'
# install.packages("base64enc")
library(base64enc)

encode_to_base64 <- function(text) {
  # Convertir le texte en octets bruts, puis encoder
  text_raw <- charToRaw(text)
  base64_encoded <- base64encode(text_raw)
  return(rawToChar(base64_encoded))
}

decode_from_base64 <- function(base64_string) {
  tryCatch({
    # Convertir la chaîne base64 en octets bruts, puis décoder
    base64_raw <- charToRaw(base64_string)
    decoded_raw <- base64decode(base64_raw)
    return(rawToChar(decoded_raw))
  }, error = function(e) {
    stop(paste("Chaîne Base64 invalide :", e$message))
  })
}

# Exemple d'utilisation
original_text <- "Hello, World!"
encoded <- encode_to_base64(original_text)
cat("Encodé :", encoded, "\n")  # SGVsbG8sIFdvcmxkIQ==

tryCatch({
  decoded <- decode_from_base64(encoded)
  cat("Décodé :", decoded, "\n")  # Hello, World!
}, error = function(e) {
  cat("Erreur :", e$message, "\n")
})

% Codage/Décodage Base64 en MATLAB
function demo_base64()
    originalText = 'Hello, World!';
    
    % Encoder
    encoded = encode_to_base64(originalText);
    fprintf('Encodé : %s\n', encoded);  % SGVsbG8sIFdvcmxkIQ==
    
    % Décoder
    try
        decoded = decode_from_base64(encoded);
        fprintf('Décodé : %s\n', decoded);  % Hello, World!
    catch e
        fprintf('Erreur : %s\n', e.message);
    end
end

function encoded = encode_to_base64(text)
    % Convertir le texte en tableau uint8 et encoder
    bytes = uint8(text);
    encoded = base64encode(bytes);
end

function decoded = decode_from_base64(base64String)
    try
        % Décoder la chaîne base64 en tableau uint8
        bytes = base64decode(base64String);
        decoded = char(bytes);
    catch
        error('Chaîne Base64 invalide');
    end
end

// Codage/Décodage Base64 en C utilisant OpenSSL
#include <stdio.h>
#include <string.h>
#include <openssl/bio.h>
#include <openssl/evp.h>
#include <openssl/buffer.h>
#include <stdint.h>

char* encode_to_base64(const char* input) {
    BIO *bio, *b64;
    BUF_MEM *bufferPtr;
    
    b64 = BIO_new(BIO_f_base64());
    bio = BIO_new(BIO_s_mem());
    bio = BIO_push(b64, bio);
    
    BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
    BIO_write(bio, input, strlen(input));
    BIO_flush(bio);
    BIO_get_mem_ptr(bio, &bufferPtr);
    
    char* result = (char*)malloc(bufferPtr->length + 1);
    memcpy(result, bufferPtr->data, bufferPtr->length);
    result[bufferPtr->length] = '\0';
    
    BIO_free_all(bio);
    
    return result;
}

char* decode_from_base64(const char* input) {
    BIO *bio, *b64;
    size_t length = strlen(input);
    char* buffer = (char*)malloc(length);
    
    b64 = BIO_new(BIO_f_base64());
    bio = BIO_new_mem_buf(input, -1);
    bio = BIO_push(b64, bio);
    
    BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL);
    int decoded_length = BIO_read(bio, buffer, length);
    
    if (decoded_length <= 0) {
        free(buffer);
        BIO_free_all(bio);
        return NULL; // Chaîne Base64 invalide
    }
    
    buffer[decoded_length] = '\0';
    
    BIO_free_all(bio);
    
    return buffer;
}

int main() {
    const char* original_text = "Hello, World!";
    
    char* encoded = encode_to_base64(original_text);
    printf("Encodé : %s\n", encoded);  // SGVsbG8sIFdvcmxkIQ==
    
    char* decoded = decode_from_base64(encoded);
    if (decoded) {
        printf("Décodé : %s\n", decoded);  // Hello, World!
        free(decoded);
    } else {
        printf("Erreur : Chaîne Base64 invalide\n");
    }
    
    free(encoded);
    
    return 0;
}

// Codage/Décodage Base64 en Rust
use base64::{encode, decode};
use std::str;

fn encode_to_base64(text: &str) -> String {
    encode(text)
}

fn decode_from_base64(base64_string: &str) -> Result<String, String> {
    match decode(base64_string) {
        Ok(bytes) => {
            match str::from_utf8(&bytes) {
                Ok(text) => Ok(text.to_string()),
                Err(e) => Err(format!("Séquence UTF-8 invalide : {}", e))
            }
        },
        Err(e) => Err(format!("Chaîne Base64 invalide : {}", e))
    }
}

fn main() {
    let original_text = "Hello, World!";
    let encoded = encode_to_base64(original_text);
    println!("Encodé : {}", encoded);  // SGVsbG8sIFdvcmxkIQ==
    
    match decode_from_base64(&encoded) {
        Ok(decoded) => println!("Décodé : {}", decoded),  // Hello, World!
        Err(e) => println!("Erreur : {}", e)
    }
}