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Hi I have an assignment for coding and I am having a hard time to figure out how to code it. My teacher wanted us to build a program that uses a list box that holds product names and a 2-D array that holds quantity in stock and price. Then in the one of the buttons in the application, which is the remove button, the item in the list box as well as the data from the array should be removed. When the user deletes an item, not only must the list loose the name of the item but the 2-D array must also be readjusted.

I am sorry. My brain just doesn't want to do what your teacher wants. If you can make sense of the following, maybe you can convince your teacher not to ask you to use 2D arrays in this instance.

Public Class Product
 'These are automatic properties
 'The compiler provides the getter, setter and backer fields.
 Public Property Name As String
 Public Property Quantiy As Integer
 Public Property Price As Double
 'ToString is a method inherited from Object. It will return a fully
 'qualified name of the Type, not what we want in a ListBox
 'The ListBox will call .ToString on Product and we will get the Name
 'property of the Product object.
 Public Overrides Function ToString() As String
 Return Name
 End Function

 Public Sub New(prodName As String, prodQuantity As Integer, prodPrice As Double)
 'We add a parameterized Constructor to make it easy to add our Product objects
 'to the ListBox. Intelisense will help out once we type the New keyword
 Name = prodName
 Quantiy = prodQuantity
 Price = prodPrice
 End Sub

End Class

Public Class Form1

 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 'The New keyword calls the Constructor of the Product class
 'so a Product object is added to the ListBox
 ListBox1.Items.Add(New Product("Bell", 30, 2.98))
 ListBox1.Items.Add(New Product("Book", 7, 200))
 ListBox1.Items.Add(New Product("Candle", 42, 14.99))
 End Sub

 Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
 'When a Product is deleted from the ListBoX with the RemoveItem button
 'this event will fire. (The index changed) -1 means nothing is selected which is
 'what happens after the delete. If Nothing is selected our cast will fail and
 'we will get an exception.
 If ListBox1.SelectedIndex <> -1 Then
 'The ListBox items are objects but underneath the objects are Products
 'so we can Cast the object back to a Product
 Dim p As Product = CType(ListBox1.SelectedItem, Product)
 'All the properties of the Procuct are then available
 MessageBox.Show($"Product Name is p.Name. There are p.Quantiy on hand. The price is p.Price:N2")
 End If
 End Sub

 Private Sub btnRemoveItem_Click(sender As Object, e As EventArgs) Handles btnRemoveItem.Click
 ListBox1.Items.Remove(ListBox1.SelectedItem)
 End Sub

End Class

This should work, though it's really the wrong way to approach this:

LBProducts = Form ListBox

lblQuantity = Form Label

lblPrice = Form Label

btnDelete = Form Button

Public Class Form1
'5 Rows, (Price, Qty)
Private ProductArray(5, 1) As Integer

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
 LBProducts.Items.Add("Apples")
 LBProducts.Items.Add("Bananas")
 LBProducts.Items.Add("Grapes")
 LBProducts.Items.Add("Oranges")
 LBProducts.Items.Add("Peaches")

 For x = 0 To 5
 ProductArray(x, 0) = x
 ProductArray(x, 1) = 1
 Next
End Sub

Private Sub LBProducts_SelectedIndexChanged(sender As Object, e As EventArgs) Handles LBProducts.SelectedIndexChanged
 Dim Index = LBProducts.SelectedIndex()

 If Index >= 0 Then
 lblPrice.Text = "Price: " & ProductArray(Index, 0)
 lblQuantity.Text = "Qty: " & ProductArray(Index, 1)
 End If

End Sub

Private Sub btnDelete_Click(sender As Object, e As EventArgs) Handles btnDelete.Click
 Dim Index = LBProducts.SelectedIndex()
 If Index >= 0 Then
 LBProducts.Items.RemoveAt(Index)

 Dim NewArray(UBound(ProductArray) - 1, 1) As Integer

 Dim i As Integer = 0
 For x = 0 To UBound(ProductArray)
 If x <> Index Then
 NewArray(i, 0) = ProductArray(x, 0)
 NewArray(i, 1) = ProductArray(x, 1)
 i += 1
 End If
 Next

 ProductArray = NewArray

 End If
End Sub
End Class