VS 2008 - Converting Byte Array To String And Back?

I am looking for something that will convert a byte array to a string and back, anything in-build that does it as this method would:

To string:
vb
Dim b = ByteArrSerialize(Obj, Compress, EncryptKey)
Dim sb As New System.Text.StringBuilder
For Each item In b
sb.Append(Chr(item))
Next

To byte:
vb
Dim b(0 To Len(TheString) - 1) As Byte
Dim bCount As Long = 0
For Each item In TheString
b(bCount) = Asc(item)
bCount += 1
Next