c# 图片转Base64 Base64转图片

先将图片转成 Base64 转成图片，再将 return 回来的 base64Str 直接赋值给  Base64ToImage(string base64) 函数（图片转出来的 base64 太长 我就不贴了，记得将图片路劲换成自己图片的路径哦，GoodNight！）

  static void Main(string[] args)
        {
            // 脸部识别
            // FaceDetect.detect();
            // 图片转 base64
          string base64Str = ImageToBase64("C:/Users/Administrator/Desktop/image.png");
            // base64转 图片
           Base64ToImage(base64Str);
        }

   /// <summary>
        /// base64 转 Image
        /// </summary>
        /// <param name="base64"></param>
        public static void Base64ToImage(string base64)
        {
            base64 = base64.Replace("data:image/png;base64,", "").Replace("data:image/jgp;base64,", "").Replace("data:image/jpg;base64,", "").Replace("data:image/jpeg;base64,", "");//将base64头部信息替换
            byte[] bytes = Convert.FromBase64String(base64);
            MemoryStream memStream = new MemoryStream(bytes);
            Image mImage = Image.FromStream(memStream);
            Bitmap bp = new Bitmap(mImage);
            bp.Save("C:/Users/Administrator/Desktop/" + DateTime.Now.ToString("yyyyMMddHHss") + ".jpg", System.Drawing.Imaging.ImageFormat.Jpeg);//注意保存路径
        }

        /// <summary>
        /// Image 转成 base64
        /// </summary>
        /// <param name="fileFullName"></param>
        public static string ImageToBase64(string fileFullName)
        {
            try
            {
                Bitmap bmp = new Bitmap(fileFullName);
                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();
                return Convert.ToBase64String(arr);
            }
            catch (Exception ex)
            {
                return null;
            }
        }