// convert key to a byte array
				int len = key.Text.Length / 2;
				if (len == 0)
					throw new ApplicationException("key must be provided");
				byte[] k = new byte[len];
				for (int i = 0; i < len; i++)
				{
					k[i] = Convert.ToByte(key.Text.Substring(i * 2, 2), 16);
				}
				summaryText += "key=" + key.Text.Trim() + "\r\n\r\n";

##</code><code>##

$key="AJDAHSDJ213718327DSFSDJFHSDKFJ87348171837"; #example
$len=length($key) / 2;
if($len == 0)
 {     print"Key must be provided";}
else  {
     for($i=0;$i<$len;$i++)      {
        $k[$i]= ?
      }