padding right with "&HBB" VB.Net - vb.net

Question

I am writing the vb.net to right padding the values. my code as follows:
Dim Ni As Byte() = { &HA6, &H02, &H01,....}
Dim Nca As Byte() = { &H12, &H00, &H02,....}
If (Ni.Length <= Nca.Length - 36) Then
Dim padLength As Integer = Nca.Length - 36 - Ni.Length
Dim padvalue As Byte() = {&HBB}
For Each w As Integer In padLength
Console.Write(Ni =Ni+ Ni.rigtPadding({&HBB}))
Next
End If
my code is not working. If Ni.Length<=Nca.Length-36, I need consist of the full Ni padded to the right with Nca-36-Ni bytes of hex value "&HBB". it is might be more than 1 "&HBB" need to be padded on the right side. and then I need the final result of Ni with the padding.
Ni is Issuer public key, Nca is CA public key ,the final result I want should be {&H6A, 02, 11, FF,....., BB,BB,BB}
Thank you very much for any help and comment.

Answer 1

Since you're using regular arrays this is relatively simple (but could be even simpler using a List(Of T)).
First you need to call Array.Resize() in order to increase the size of the array. Then you can use a regular For loop to fill the new space.
Dim prevLength As Integer = Ni.Length 'Store the previous length so we can start looping from it.
Array.Resize(Ni, Ni.Length + padLength) 'Take the original length and increase it by how much needs to be padded.
'Iterate from the beginning of the padding to the new end of the array.
For i = prevLength To Ni.Length - 1
Ni(i) = &HBB
Next
I also suggest you read up a little on how arrays work: Arrays in Visual Basic - Microsoft Docs.

Answer 2

You can manually resize NCI using Redim Preserve and set the padding character:
Dim Padding as Byte = &HBB
Dim Nca As Byte() = { &H12, &H00, &H02,....}
Dim Ni As Byte() = { &HA6, &H02, &H01,....}
Dim len = Nca.Length - 36
if (len > Ni.Length) Then
Redim Preserve Ni(len+1)
For i As Integer = len to Ni.Length-1
Ni(i) = Padding
Next
End if
Or you can use LINQ:
Dim Padding as Byte = &HBB
Dim Pad =Function(i) If(i < Nca.Length, Nca(i), padding)
Dim Nca As Byte() = { &H12, &H00, &H02,....}
Dim len as integer = Nca.Length - 36
if len > Ni.Length Then Ni = Enumerable.Range(0, len+1).Select(Pad).ToArray()