วิธีบันทึกไฟล์รูปด้วย C# .net ด้วยวิธีต่างๆ

1.from byte[]:

byte[] img = Convert.FromBase64String(s);
System.IO.File.WriteAllBytes(@"C:\image.bmp", img);

2.

ImageConverter img_converter = new ImageConverter();
byte[] bytes = (byte[])img_converter.ConvertTo(<strong class="highlight">image</strong>, typeof(byte[]));  
File.WriteAllBytes(savefil.FileName, bytes);

3.

var imageBytes = File.ReadAllBytes("bitmap.bmp");
var image = imageBytes.ToImage();
image.Save("output.bmp");

from some file:
4.1

Image.Save(@"FilePath", ImageFormat.Jpeg);

4.2.

Image bitmap = Image.FromFile("C:\\MyFile.bmp");
bitmap.Save("C:\\MyFile2.bmp");  

5. from pictureBox:

pictureBox1.Image.Save(@"path + imageName",ImageFormat.Jpeg);

ที่มา

http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/73cb15de-5bea-4d82-b5ef-821deb09ce44