Android Question Conversion from RC4 text to RC4 byte array

 Sub rc4(message As String, password As String) As String

      Dim i As Int
      i = 0
        Dim j As Int
      j = 0
        Dim cipher As StringBuilder
      cipher.Initialize
        Dim returnCipher As String
      returnCipher = ""
    
        Dim sbox(256) As Int
        Dim key(256) As Int

        Dim intLength As Int
      intLength = password.Length

        Dim a As Int
      a = 0
        Do While a <= 255

            Dim ctmp As Char
         ctmp = password.SubString(a Mod intLength)
            key(a) = Asc(ctmp)
            sbox(a) = a
            a = a + 1
        Loop

        Dim x As Int
      x = 0

        Dim b As Int
      b = 0
        Do While b <= 255
            x = (x + sbox(b) + key(b)) Mod 256
            Dim tempSwap As Int
         tempSwap = sbox(b)
            sbox(b) = sbox(x)
            sbox(x) = tempSwap
            b = b + 1
          Loop

        a = 1

        Do While a <= message.Length

            Dim itmp As Int
         itmp = 0

            i = (i + 1) Mod 256
            j = (j + sbox(i)) Mod 256
            itmp = sbox(i)
            sbox(i) = sbox(j)
            sbox(j) = itmp

            Dim k As Int
         k = sbox((sbox(i) + sbox(j)) Mod 256)

            Dim ctmp As Char
         ctmp = message.Substring(a - 1)

            itmp = Asc(ctmp)

            Dim cipherby As Int
         cipherby = Bit.Xor(itmp, k)

            cipher.Append(Chr(cipherby))
            a = a + 1
        Loop

        returnCipher = cipher.ToString
      
      Return returnCipher

    End Sub