C Implementation String and Picture Base64 Transcoding Operation Example

In this paper, an example of C # to achieve string and picture Base64 encoding conversion operation. Share it for your reference, as follows:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Drawing.Imaging;
namespace base64_img
{
  public partial class Form1 : Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    // Picture   Convert to   base64 Coded text 
    private void button1_Click(object sender, EventArgs e)
    {
      OpenFileDialog dlg = new OpenFileDialog();
      dlg.Title = " Select the picture to convert ";
      dlg.Filter = "Image files (*.jpg;*.bmp;*.gif)|*.jpg*.jpeg;*.gif;*.bmp|AllFiles (*.*)|*.*";
      if (DialogResult.OK == dlg.ShowDialog())
      {
        ImgToBase64String(dlg.FileName);
      }
    }
    // Picture   Convert to   base64 Coded text 
    private void ImgToBase64String(string Imagefilename)
    {
      try
      {
        Bitmap bmp = new Bitmap(Imagefilename);
        this.pictureBox1.Image = bmp;
        FileStream fs = new FileStream(Imagefilename + ".txt", FileMode.Create);
        StreamWriter sw = new StreamWriter(fs);
        MemoryStream ms = new MemoryStream();
        bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
        byte[] arr = new byte[ms.Length];
        ms.Position = 0;
        ms.Read(arr, 0, (int)ms.Length);
        ms.Close();
        String strbaser64 = Convert.ToBase64String(arr);
        sw.Write(strbaser64);
        sw.Close();
        fs.Close();
        MessageBox.Show(" Successful conversion !");
      }
      catch (Exception ex)
      {
        MessageBox.Show("ImgToBase64String  Conversion failed /nException:" + ex.Message);
      }
    }
    //base64 Coded text   Convert to    Picture 
    private void button2_Click(object sender, EventArgs e)
    {
      OpenFileDialog dlg = new OpenFileDialog();
      dlg.Title = " Select the to convert base64 Coded text ";
      dlg.Filter = "txt files|*.txt";
      if (DialogResult.OK == dlg.ShowDialog())
      {
        Base64StringToImage(dlg.FileName);
      }
    }
    //base64 Coded text   Convert to    Picture 
    private void Base64StringToImage(string txtFileName)
    {
      try
      {
        FileStream ifs = new FileStream(txtFileName, FileMode.Open, FileAccess.Read);
        StreamReader sr = new StreamReader(ifs);
        String inputStr = sr.ReadToEnd();
        byte[] arr = Convert.FromBase64String(inputStr);
        MemoryStream ms = new MemoryStream(arr);
        Bitmap bmp = new Bitmap(ms);
        bmp.Save(txtFileName + ".jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
        //bmp.Save(txtFileName + ".bmp", ImageFormat.Bmp);
        //bmp.Save(txtFileName + ".gif", ImageFormat.Gif);
        //bmp.Save(txtFileName + ".png", ImageFormat.Png);
        ms.Close();
        sr.Close();
        ifs.Close();
        this.pictureBox1.Image = bmp;
        MessageBox.Show(" Conversion succeeded! ");
      }
      catch (Exception ex)
      {
        MessageBox.Show("Base64StringToImage  Conversion failed /nException : "+ex.Message);
      }
    }
  }
}

PS: Here are several practical base64 online encoding and decoding tools for everyone to use:

BASE64 encoding and decoding tool:
http://tools.ofstack.com/transcoding/base64

Online image conversion BASE64 tool:
http://tools.ofstack.com/transcoding/img2base64

Base64 Online Coding and Decoding UTF-8 Version:
http://tools.ofstack.com/tools/base64_decode-utf8.php

Base64 Online Coding and Decoding gb2312 Version:
http://tools.ofstack.com/tools/base64_decode-gb2312.php

For more readers interested in C # related content, please check the topics on this site: "Summary of C # Coding Operation Skills", "Summary of XML File Operation Skills in C #", "Tutorial on Usage of C # Common Controls", "Tutorial on Usage of WinForm Controls", "Tutorial on Data Structures and Algorithms", "Introduction to C # Object-Oriented Programming" and "Summary of Thread Use Skills in C # Programming"

I hope this article is helpful to everyone's C # programming.