I'm trying to write the below C# code in perl, what is the C# equivalent for Convert.ToByte(key.Text.Substring(i * 2, 2), 16); in perl.
Any insight is much appreciated.
Thanks.

C# code 
// convert key to a byte array
                int len = key.Text.Length / 2;
                if (len == 0)
                    throw new ApplicationException("key must be provid
+ed");
                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";

[download]
Perl code I got so far # convert key to a byte array 
$key="AJDAHSDJ213718327DSFSDJFHSDKFJ87348171837"; #example
$len=length($key) / 2;
if($len == 0)
 {     print"Key must be provided";}
else  {
     for($i=0;$i<$len;$i++)      {
        $k[$i]= ?
      }

[download]

Also how do you pass the byte array as a key value to sha256 hash, Join the array values ? $key_value=@k; $digest=hmac_sha256_base64($data,$key_value);

In reply to String to Byte array by kpaxian25

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