Base64编码的字符串与图片的转换 C#

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); } } } }