Visual Basic.NET - Como obtener la suma de un string en hexadecimal

Function SumaHex(ByVal Cadena As String) As Long

    Dim suma As Long = 0

    For l As Integer = 0 To Cadena.Length - 1 Step 2

        suma += CInt("&H" & Cadena.Substring(l, 2))

    Next l

    Return suma

End Function

String="0E00005031544D50434B2E733139"

Dim suma As Integer=0

Dim sumaHex As String

Dim i As Integer

For i=0 To inpu.Length-2 Step 2

   suma+=Convert.ToInt32(inpu.SubString(i,2),16)

Next

sumaHex=Hex(suma)