C#文件转byte数组，byte数组转文件

//文件转byte数组
FileStream fs = new FileStream(filepath, FileMode.Open, FileAccess.Read);
byte[] bytebuffer;
bytebuffer = new byte[fs.Length];
fs.Read(bytebuffer, 0, (int)fs.Length);
fs.Close();

//byte数组转文件
File.WriteAllBytes(@"c:\test.jpg", bytebuffer);