How to create multiple labels - vb.net

Question

I'm new to "coding/programming". I'm trying to make a functional program - I call it "a point to pay". It's like those supermarket programs where they register the thing you are going to buy. So i need to create some labels to register products.
The code I have:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click ''When i click the button
If CantidadVer1.Text = 0 Then ''this verifies how many Labels i have created
CantidadVer1.Text = +1 ''this updates the verification
Dim lbl1 As New Label ''this creates the labels
lbl1.Size = New System.Drawing.Size(159, 23)
lbl1.Text = (Product.Text) ''product.text is a TextBox
lbl1.Location = New System.Drawing.Point(12, 80 + 20) '' i add 20 more everytime i create a label
Me.Controls.Add(lbl1)
ElseIf CantidadVer1.Text = 2 Then ''at this point it creates the label but "crashes" (It dosent work anymore)
CantidadVer1.Text = +1
Dim lbl2 As New Label
lbl2.Size = New System.Drawing.Size(159, 23)
lbl2.Text = (Product.Text)
lbl2.Location = New System.Drawing.Point(12, 80 + 40)
Me.Controls.Add(lbl2)
ElseIf CantidadVer1.Text = 2 Then
CantidadVer1.Text = +1
Dim lbl3 As New Label
lbl3.Size = New System.Drawing.Size(159, 23)
lbl3.Text = (Product.Text)
lbl3.Location = New System.Drawing.Point(12, 80 + 60)
Me.Controls.Add(lbl3)
ElseIf CantidadVer1.Text = 3 Then
CantidadVer1.Text = +1
Dim lbl4 As New Label
lbl4.Size = New System.Drawing.Size(159, 23)
lbl4.Text = (Product.Text)
lbl4.Location = New System.Drawing.Point(12, 80 + 80)
Me.Controls.Add(lbl4)
ElseIf CantidadVer1.Text = 4 Then
CantidadVer1.Text = +1
Dim lbl4 As New Label
lbl4.Size = New System.Drawing.Size(159, 23)
lbl4.Text = (Product.Text)
lbl4.Location = New System.Drawing.Point(12, 80 + 100)
Me.Controls.Add(lbl4)
End If
End Sub
So I execute it and then it creates 2 labels and then crashes.
It is supposed to create 5 labels .
Is there an easier way to create multiple labels without making the program crash?

Answer 1

In your code I only see one label created every time. I don't think the code crashes. Remember in an IF block, if the condition is met in the first part, it skips all subsequent ElseIf conditions.
With a little research, you'll see that the best option would be to use a DataGridView instead of a bunch of labels. You could simply add a new row for each item. Lets say you have a datagridview named DGV_Product with 3 textbox columns for product, quantity and price:
Dim price as Double = 1.99
Dim product as String = "Apple"
Dim qty as integer = 3
DGV_Product.Rows.Add(New String() {product, Cstr(qty), CStr(price)})
That adds a row containing "Apple, 3, 1.99"
But if you insist on using labels, This would work better:
1) Set The following variable at a class level.
Dim lbl_pos as integer
2) In your form Load event handler set the value to 20 less than where you want your first label to appear:
lbl_pos = 80 ' gathered from your code
3) Then in your click event handler of the button you increment the new label's position by 20 before adding the new label.
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
lbl_pos = lbl_pos + 20 'increment the position
Dim lbl as New Label
With lbl
.Text = "Your Text"
.Location = New Point(10,lbl_pos) '(left position, top position)
' And so Forth
End With
me.controls.add(lbl)
End Sub
With this approach you can add as many labels as you like without a bunch of If-ElseIf blocks.
I hope you rethink your approach and go with the DataGridView instead as it's much more practical and you can add as many rows as you like without hassle.

Answer 2

You have an error in your code .. The line
ElseIf CantidadVer1.Text = 2 Then ''at this point it creates the label but "crashes" (It dosent work anymore
should be
ElseIf CantidadVer1.Text = 1 Then ''at this point it creates the label but "crashes" (It dosent work anymore)

Answer 3

If you dont set the value for CantidadVer1 in the begining. Its value = "" not 0. so it will be the bug if you dont put 0 to the CantidadVer1.text
the first if maybe like this
If CantidadVer1.Text = "" OR CantidadVer1.Text = 0 Then

Answer 4

Your PTP is poorly designed. All the answers here are trying to solve your problem by looking based on what you've done.
But your model is kinda based on your what's in your view. For example, have you planned how you will retrieve all the added products ? The history is inside your view : good luck with that.
That's why I suggest to review your design. For example :
Use a List in your code behind to save your data. Your button_click should only do that (with some validations).
Use a repeater in your view. Bind that repeater to your List : and voila. Your repeater will take care of creating all the label corresponding to all the added products.