Calculating (add) HEX values-CodePudding

i am trying to do the following:Looking up values in a .txt file, such as "DD" which will be written into a string variable, and then converted into a Byte variable. I then want to add to this, for example BB 10 = CB

For testing, my code is the following

Public reqw As String = "BB" 'normally comes from the txt. file
Public btansw as byte
Public finansw as string 

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    Dim MyByte As Byte
    If Byte.TryParse(reqw, System.Globalization.NumberStyles.AllowHexSpecifier, Nothing, MyByte) Then
        btansw = MyByte 
    Else
        RichTextBox3.Text &= "Err2"

    End If

This code converts the string "BB" into bytes. The acutal problem is the following:

finansw = Microsoft.VisualBasic.Conversion.Hex(btansw  10) 

    RichTextBox3.Text &= finansw

This gives me "C5" as result in the RichTextBox but it is supposed to be "CB".

Can someone explain what i am doing wrong?

CodePudding user response：

You are adding 10, i.e. ten, so the result is correct. If what you actually want to add is 0x10, i.e. sixteen, then you need to actually use a hex value. In VB, you use the &H prefix to indicate a hex literal.

finansw = (btansw   &H10).ToString("X2")

Let's not write our VB.NET like we were still using VB6.