文件转byte[]

byte[] pB = null;
if (!string.IsNullOrEmpty(pathword))//pathword文件路径
{

     FileStream p = null;
     try
      {
           p = new FileStream(pathword, FileMode.Open, FileAccess.Read);
           BinaryReader br = new BinaryReader(p);
           br.BaseStream.Seek(0, SeekOrigin.Begin);
           pB = br.ReadBytes((int)br.BaseStream.Length);
       }
       catc
       {
            pB = null;
       }
       finally
       {
            if (p != null)
            {
                 p.Close();
            }
        }
}