[RESOLVED] How to compare combobox item to the first 10 digits value in textbox

[BONITO]

Hi All,

I want to make a program that will compare the selected items of combo box to the first 10 digits value of text box, user can input up to 24 digits serial no. from the text box. and I will set default value to the items of combo box. example see my code below.
I don't know what to use if else , or select case,
Please help me thank you in advance.

Public Class Form1 
    Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click 
        ' Case 1 
        If cmbModel.SelectedItem.text <> "" Then 
            MsgBox("Choose model") 
        End If 
        ' case 2 
        If cmbModel.SelectedItem.text = "PBGS01 (MR SENSOR)" Then 
            If txtSerialNo.Text = "11150PP20000%" Then 
                MsgBox("Success") 
 
            Else 
                MsgBox("Model and Serial no not match !") 
            End If 
        End If 
        ' case 3 
        If cmbModel.SelectedItem.text = "PBGE01 (ECU BOARD)" Then 
            If txtSerialNo.Text = "38700BD20101%" Then 
                MsgBox("Success") 
 
            Else 
                MsgBox("You select wrong Model") 
            End If 
        End If 
        ' case 4 
        If cmbModel.SelectedItem.text = "PBGM01 (MCU BOARD)" Then 
            If txtSerialNo.Text = "12110PP20000%" Then 
                MsgBox("Success") 
 
            Else 
                MsgBox("You select wrong Model") 
            End If 
        End If 
    End Sub 
End Class

here is my form look likes.