Error Code and how to get it to disappear

[pooker75]

Here is the code again and the error I get is Invalid Argument=Value of "-1" is not valid for 'index' Parameter Name:index

Please advise the code so this error goes away and the program will still execute correctly. Other suggestions posted either still give errors or the program does not execute once I put the suggestion in. Thanks for your help.
Jo Ann


Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

'load the item into the combobox
Try

vinStreamreader = New StreamReader("car.txt")
DisplayRecord()
Catch ex As Exception
'File is not found.
MessageBox.Show(ex.Message)
End Try


End Sub
Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
'Read the next record.

DisplayRecord()
End Sub

Private Sub DisplayRecord()
'Read and display the next record.
Dim vinString As String
Do While vinStreamreader.Peek <> -1
vinString = vinStreamreader.ReadLine()
Me.ComboBox1.Text = vinString
Me.ComboBox1.Items.Add(ComboBox1.Text)


Me.ListBox1.Items.Add(vinStreamreader.ReadLine())
Me.ListBox2.Items.Add(vinStreamreader.ReadLine())
Me.ListBox3.Items.Add(vinStreamreader.ReadLine())

Loop
'Display labels
Me.Label4.Text = Me.ListBox1.Items(Me.ComboBox1.SelectedIndex)
Me.Label5.Text = Me.ListBox2.Items(Me.ComboBox1.SelectedIndex)
Me.Label6.Text = Me.ListBox3.Items(Me.ComboBox1.SelectedIndex)
End Sub


End Class

[kadghar]

Here is the code again and the error I get is Invalid Argument=Value of "-1" is not valid for 'index' Parameter Name:index

...

When the combobox has no selected item, its index is -1.
I think this problem can be solved by changing Me.Combobox1.SelectedIndex with an integer, lets say K, and :

dim K as integer
K= me.combobox1.selectedindex
if K<0 then K = 0

This way, if there's no item selected, it'll use the first of the list. Or you can just exit the sub if the index is -1.

HTH

[pooker75]

I tried this code at the very beginning and at each sub and I still get the message. Good idea but does not eliminate the error. Jo Ann

[kadghar]

I tried this code at the very beginning and at each sub and I still get the message. Good idea but does not eliminate the error. Jo Ann

could you put again your code, but with code tags, so it'll numerate the lines, and tell us in what line does the error first appear??

Thanks =)