converting to integer

[tragic54]

Alright so i've done this in some of my recent programs with option strict on and for some reason When i debug and select the option from the combo box, it crashes and gives me a 'Input String was not in the correct format' error. Ive tried declaring the variables as strings and converting the textbox to integer from there and still get the same thing. I'm just trying to get a value to store it in that variable so i can use it for later calculations. Theres a lot more to it, but considering i'm getting this so early i don't wanna continue until i get it right.

Option Strict On
Option Explicit On
 
Public Class Form1
 
    Private Sub cboCommute_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboCommute.SelectedIndexChanged
 
        Dim intCommuteChoice As Integer
        intCommuteChoice = Me.cboCommute.SelectedIndex
        Select Case intCommuteChoice
            Case 0
                CarCommute()
 
        End Select
 
    End Sub
 
 
    Private Sub CarCommute()
        Me.GroupBox1.Visible = True
 
        Dim intlabel1 As Integer
        Dim intlabel2 As Integer
 
        intlabel1 = Convert.ToInt32(Me.Label1.Text)
        intlabel2 = Convert.ToInt32(Me.Label2.Text)
 
    End Sub
 
End Class
 

[Killer42]

Which line throws the error?

[tragic54]

25. I guess ill just declare variables as strings and take the input from the message boxes and convert them to integers when doing the calculations. Just wondering what the syntax is to force a textbox to accept an integer value instead of string.

[QVeen72]

Hi,

Try This :

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
        If InStr("0123456789", e.KeyChar.ToString) <= 0 Then
            e.Handled = True
        End If
    End Sub
 

Regards
Veena

[QVeen72]

Hi,

If you are getting error on 25 and 26th line, you can just use the "Val" function like this..:

intlabel1 = Val(Me.Label1.Text)
intlabel2 = Val(Me.Label2.Text)
 

Regards
Veena

[Killer42]

Assuming it's still available in your version (I use VB6) I'd recommend using the Masked Edit control rather than a textbox. It allows much better control over what is input.

[kadghar]

what i've found easier is using CType(Var, Type) to make all the type changes you need while using Option Strict (yeah, the easy way out).

[Killer42]

Generally speaking though, I think it's better practice to restrict user input to what is acceptable, rather than waiting until they've entered something then complaining about it.