Android Question Converting a character to an integer

 Dim iCheckSumTotal As Integer
        Dim sCheckSumTotal As String
        Dim sCheckSumResponse As String
        Dim i As Integer
        Dim iCommandLength As Integer
        iCommandLength = command.Length
        i = 0

        While i < iCommandLength
            iCheckSumTotal = iCheckSumTotal + Convert.ToInt32(Convert.ToChar(command.Substring(i, 1)))
            i += 1
        End While

  Dim iCheckSumTotal As Int
        Dim sCheckSumTotal As String
        Dim sCheckSumResponse As String
        Dim i As Int
        Dim iCommandLength As Int
        iCommandLength = command.Length
        i = 0

        Do While i < iCommandLength
            Dim charatt As String = command.CharAt(i)
           
            iCheckSumTotal = iCheckSumTotal + charatt
            i = i+ 1
        Loop