Index out of bounds of the array vb.net - vb.net

Question

I am getting an error at this line:
CheckedListBox3.Items.Remove(CheckedListBox3.CheckedItems(0))
I don't understand why because it does read the first two but not the third... the index of my checkedlistbox1, 2 and 3 is 3 so that makes it (0), (1), and (2) in each while...
Please help me out and tell me where i am wrong because i don't understand how it's possible that he can find the index of the first and second listbox but can't find the index of the third listbox
This is my code:
cmd = New SqlCommand("SELECT serienaam, ouderdom, aantal FROM klantserie Where klantnummer = '" & klantnummer & "' ", con)
Dim ttr As SqlDataReader = cmd.ExecuteReader()
While ttr.Read = True
CheckedListBox1.Items.Add(ttr.Item("serienaam")) "serienaam" = a-map or c-map
CheckedListBox2.Items.Add(ttr.Item("ouderdom")) "ouderdom" = week1 - week16
CheckedListBox3.Items.Add(ttr.Item("aantal")) "aantal" = 1 - 10
End While
added the code that adds the items to the checkedlistbox
Private Sub Button79_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button79.Click
While CheckedListBox1.CheckedItems.Count - 1 >= 0 ''i have changed this line a few times don't really know if it matters to the outcome of the error''
Dim serienaam
Dim oud
Dim aantal As Integer
Dim bedrag As Decimal
Dim totaal As Decimal
Try
serienaam = CheckedListBox1.CheckedItems(0)
oud = CheckedListBox2.CheckedItems(0)
aantal = CheckedListBox3.CheckedItems(0)
Catch ex As Exception
End Try
cmd = New SqlCommand("SELECT " & oud & " FROM series Where naamserie = '" & serienaam & "' ", con)
Dim sdr As SqlDataReader = cmd.ExecuteReader()
If sdr.Read = True Then
Dim week = sdr.Item(oud)
bedrag = week * aantal
totaal = Label69.Text
totaal = totaal - bedrag
sdr.Close()
Label69.Text = totaal
End If
CheckedListBox1.Items.Remove(CheckedListBox1.CheckedItems(0))
CheckedListBox2.Items.Remove(CheckedListBox2.CheckedItems(0))
Try
CheckedListBox3.Items.Remove(CheckedListBox3.CheckedItems(0)) ''<<<----error
this try doesn't do anything actually except for the fact that im not getting any errors anymore
Catch ex As Exception
If ex IsNot Nothing Then
Dim s = CheckedListBox3.Items.Count
CheckedListBox3.SelectedItem = s
CheckedListBox3.Items.Remove(s)
End If
End Try
End While
End Sub
this is the code for the check
Private Sub CheckedListBox1_ItemCheck(ByVal sender As Object, ByVal e As ItemCheckEventArgs) Handles CheckedListBox1.ItemCheck
Dim index As Integer = e.Index
CheckedListBox2.SetItemChecked(index, e.NewValue)
CheckedListBox3.SetItemChecked(index, e.NewValue)
End Sub
my solution since it didn't work.
Private Sub Button76_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button76.Click
Dim serienaam
Dim oud
Dim aantal As Integer
Dim bedrag As Decimal
Dim totaal As Decimal
Dim t As String
serienaam = ComboBox6.SelectedItem
oud = ComboBox7.SelectedItem
aantal = TextBox45.Text
cmd = New SqlCommand("SELECT " & oud & " FROM series Where naamserie = '" & serienaam & "' ", con)
Dim sdr As SqlDataReader = cmd.ExecuteReader()
If sdr.Read = True Then
Dim week = sdr.Item(oud)
bedrag = week
totaal = Label69.Text
totaal = totaal + bedrag * aantal
sdr.Close()
Label69.Text = totaal
t = " '" & serienaam & "' '" & oud & "' '" & aantal & "' "
CheckedListBox1.Items.Add(t)
End If
End Sub
Private Sub Button79_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button79.Click
While CheckedListBox1.CheckedItems.Count <> 0
Dim klantnr As String
Dim serienaam As String
Dim oud As String
Dim list As String
Dim aantal As Integer
Dim bedrag As Decimal
Dim totaal As Decimal
klantnr = TextBox32.Text
list = CheckedListBox1.CheckedItems(0)
Dim strlist = list.Split("'")
For count = 0 To strlist.Length - 1
serienaam = strlist(1)
oud = strlist(3)
aantal = strlist(5)
Next
cmd = New SqlCommand("SELECT " & oud & " FROM series Where naamserie = '" & serienaam & "' ", con)
Dim sdr As SqlDataReader = cmd.ExecuteReader()
If sdr.Read = True Then
Dim week = sdr.Item(oud)
bedrag = week * aantal
totaal = Label69.Text
totaal = totaal - bedrag
sdr.Close()
Label69.Text = totaal
End If
cmd = New SqlCommand("DELETE FROM klantserie Where klantnummer = '" & klantnr & "' And serienaam = '" & serienaam & "' And ouderdom = '" & oud & "' And aantal = '" & aantal & "' ", con)
If con.State = ConnectionState.Closed Then con.Open()
cmd.ExecuteNonQuery()
ShowData()
CheckedListBox1.Items.Remove(CheckedListBox1.CheckedItems(0))
End While
End Sub

Answer 1

Not sure if you've fixed this but I tried to reproduce the problem and failed. Here's what I used:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
CheckedListBox1.Items.Clear()
CheckedListBox1.Items.Add("List1Item1")
CheckedListBox1.Items.Add("List1Item2")
CheckedListBox1.Items.Add("List1Item3")
CheckedListBox2.Items.Clear()
CheckedListBox2.Items.Add("List2Item1")
CheckedListBox2.Items.Add("List2Item2")
CheckedListBox2.Items.Add("List2Item3")
CheckedListBox3.Items.Clear()
CheckedListBox3.Items.Add("List3Item1")
CheckedListBox3.Items.Add("List3Item2")
CheckedListBox3.Items.Add("List3Item3")
End Sub
Private Sub CheckedListBox1_ItemCheck(sender As Object, e As ItemCheckEventArgs) Handles CheckedListBox1.ItemCheck
Dim index As Integer = e.Index
CheckedListBox2.SetItemChecked(index, e.NewValue)
CheckedListBox3.SetItemChecked(index, e.NewValue)
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
While CheckedListBox1.CheckedItems.Count <> 0
Dim serienaam As String
Dim oud As String
Dim aantal As String
serienaam = CheckedListBox1.CheckedItems(0)
oud = CheckedListBox2.CheckedItems(0)
aantal = CheckedListBox3.CheckedItems(0)
CheckedListBox1.Items.Remove(CheckedListBox1.CheckedItems(0))
CheckedListBox2.Items.Remove(CheckedListBox2.CheckedItems(0))
CheckedListBox3.Items.Remove(CheckedListBox3.CheckedItems(0))
End While
End Sub
This works just fine. I can add items to the boxes using Button 1 and then check anything in the first box (which checks the corresponding items in the other boxes based on index - couldn't be bothered to wire up lists 2 and 3 to do the same) and then I can delete the checked items with no errors using Button2. The only change to yours is obviously I'm using mocked data, not SQL queries.