C#实现字符串与图片的Base64编码转换操作示例

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();    }    //图片 转为  base64编码的文本    private void button1_Click(object sender, EventArgs e)    {      OpenFileDialog dlg = new OpenFileDialog();      dlg.Title = "选择要转换的图片";      dlg.Filter = "Image files (*.jpg;*.bmp;*.gif)|*.jpg*.jpeg;*.gif;*.bmp|AllFiles (*.*)|*.*";      if (DialogResult.OK == dlg.ShowDialog())      {        ImgToBase64String(dlg.FileName);      }    }    //图片 转为  base64编码的文本    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("转换成功!");      }      catch (Exception ex)      {        MessageBox.Show("ImgToBase64String 转换失败/nException:" + ex.Message);      }    }    //base64编码的文本 转为  图片    private void button2_Click(object sender, EventArgs e)    {      OpenFileDialog dlg = new OpenFileDialog();      dlg.Title = "选择要转换的base64编码的文本";      dlg.Filter = "txt files|*.txt";      if (DialogResult.OK == dlg.ShowDialog())      {        Base64StringToImage(dlg.FileName);      }    }    //base64编码的文本 转为  图片    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("转换成功！");      }      catch (Exception ex)      {        MessageBox.Show("Base64StringToImage 转换失败/nException："+ex.Message);      }    }  }}