C# imgage图片转base64字符/base64字符串转图片另存

	   //图片转为base64编码的字符串protected string ImgToBase64String(string Imagefilename){try{Bitmap bmp = new Bitmap(Imagefilename);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;}}//base64编码的字符串转为图片protected Bitmap Base64StringToImage(string strbase64){try{byte[] arr = Convert.FromBase64String(strbase64);MemoryStream ms = new MemoryStream(arr);Bitmap bmp = new Bitmap(ms);bmp.Save(@"d:\test.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);//bmp.Save(@"d:\"test.bmp", ImageFormat.Bmp);//bmp.Save(@"d:\"test.gif", ImageFormat.Gif);//bmp.Save(@"d:\"test.png", ImageFormat.Png);ms.Close();return bmp;}catch (Exception ex){return null;}}