C#中图片、二进制与字符串的相互转换方法

protected void Button1_Click(object sender, EventArgs e){  //图片转二进制  byte[] imageByte = GetPictureData(Server.MapPath("./uploadfile/111.png"));  //二进制转换成字符串  string picStr = Convert.ToBase64String(imageByte);  //输出字符串  Response.Write(picStr);  //字符串转二进制  byte[] imageBytes = Convert.FromBase64String(picStr);  //读入MemoryStream对象  MemoryStream memoryStream = new MemoryStream(imageBytes, 0, imageBytes.Length);  memoryStream.Write(imageBytes, 0, imageBytes.Length);  //二进制转成图片保存  System.Drawing.Image image = System.Drawing.Image.FromStream(memoryStream);  image.Save(Server.MapPath("./uploadfile/222.png"));}/// <summary>/// 二进制流转图片/// </summary>/// <param name="streamByte">二进制流</param>/// <returns>图片</returns>public System.Drawing.Image ReturnPhoto(byte[] streamByte){  System.IO.MemoryStream ms = new System.IO.MemoryStream(streamByte);  System.Drawing.Image img = System.Drawing.Image.FromStream(ms);  return img;}/// <summary>/// 图片转二进制/// </summary>/// <param name="imagepath">图片地址</param>/// <returns>二进制</returns>public byte[] GetPictureData(string imagepath){  //根据图片文件的路径使用文件流打开，并保存为byte[]  FileStream fs = new FileStream(imagepath, FileMode.Open);//可以是其他重载方法  byte[] byData = new byte[fs.Length];  fs.Read(byData, 0, byData.Length);  fs.Close();  return byData;}/// <summary>/// 图片转二进制/// </summary>/// <param name="imgPhoto">图片对象</param>/// <returns>二进制</returns>public byte[] PhotoImageInsert(System.Drawing.Image imgPhoto){  //将Image转换成流数据，并保存为byte[]  MemoryStream mstream = new MemoryStream();  imgPhoto.Save(mstream, System.Drawing.Imaging.ImageFormat.Bmp);  byte[] byData = new Byte[mstream.Length];  mstream.Position = 0;  mstream.Read(byData, 0, byData.Length);  mstream.Close();  return byData;}