csharp:Convert Image to Base64 String and Base64 String to Image

 /// <summary>
        /// 圖像轉成二進制數組
        /// </summary>
        /// <param name="imageIn"></param>
        /// <returns></returns>
        public byte[] imageToByteArray(System.Drawing.Image imageIn)
        {
            MemoryStream ms = new MemoryStream();
            imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
            return ms.ToArray();
        }
        /// <summary>
        /// 二進制數據轉成圖像
        /// </summary>
        /// <param name="byteArrayIn"></param>
        /// <returns></returns>
        public System.Drawing.Image byteArrayToImage(byte[] byteArrayIn)
        {
            MemoryStream ms = new MemoryStream(byteArrayIn);
            System.Drawing.Image returnImage = System.Drawing.Image.FromStream(ms);
            return returnImage;
        }
        /// <summary>
        /// 圖像轉成Base64字符
        /// </summary>
        /// <param name="image"></param>
        /// <param name="format"></param>
        /// <returns></returns>
        public string ImageToBase64(Image image,  System.Drawing.Imaging.ImageFormat format)
        {
            using (MemoryStream ms = new MemoryStream())
            {
                // Convert Image to byte[]
                image.Save(ms, format);
                byte[] imageBytes = ms.ToArray();

                // Convert byte[] to Base64 String
                string base64String = Convert.ToBase64String(imageBytes);
                return base64String;
            }
        }
        /// <summary>
        /// Base64字符轉成圖像
        /// </summary>
        /// <param name="base64String"></param>
        /// <returns></returns>
        public Image Base64ToImage(string base64String)
        {
            // Convert Base64 String to byte[]
            byte[] imageBytes = Convert.FromBase64String(base64String);
            MemoryStream ms = new MemoryStream(imageBytes, 0,
              imageBytes.Length);

            // Convert byte[] to Image
            ms.Write(imageBytes, 0, imageBytes.Length);
            Image image = Image.FromStream(ms, true);
            return image;
        }

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