Control Arrays

Control Arrays

• kuria

  They chagned it because collections are far better.

  To get your answer, just take your exact thread title and put it in the search bar of this forum. Your answer is on the first page of results.

  
  
  

• amb_lew

  That does work but it if I am not mistaken it means that the picture boxes are created at runtime. I would rather i craeate controls in the form, my program will run better that way.
  i managed to do it: took me 2 days but I managed. i am going to use buttons instead of picture boxes so that i can use tha TabIndex of the buttons to act as "indexes", picture boxes dont have tabindexes.
  
  dim a as integer 'tabindex for the buttons btwn 0 and 150
  dim value as integer
  
  Private Sub Timesr1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
  Randomize()
  value = Int((4 * Rnd()) + 1) 'generates a rando number between 1 and 4
  Dim Box As Button
  For Each Box In Me.Controls 'find all the buttons in the form
  If TypeOf Box Is Button Then 'this part might not be neccesary as Box is defined as button
  If Box.TabIndex = a Then 'if the tabindex of the box is between 0 and 150 then change its background image
  If Value = 1 Then Box.BackgroundImage = picBlue.Image
  If Value = 2 Then Box.BackgroundImage = picRed.Image
  If Value = 3 Then Box.BackgroundImage = picGreen.Image
  If Value = 4 Then Box.BackgroundImage = picWhite.Image
  End If
  End If
  Next
  a += 1
  If a = 151 Then Timer1.Enabled = False
  Exit Sub
  End Sub
  
  its easier to do it this way
  Thanks
  
  

• Wai Hon

  Hi-

  This is definitely a FAQ.

  Here are a few details to get you started:

  - You can use the Collections.Generic.List(Of T) object as a nice container for your pictureboxes. Simply replace T with the type you want to use, like PictureBox. E.g.:

  Dim picBox As New Collections.Generic.List(Of PictureBox)

  - You can work with generic List objects by index similarly to the VB6 array, and you even get nice Intellisense now, e.g.

  picBox(2).Image

  - Don't forget that arrays and collections in VB 2005 are zero-based, so they start indexing at 0.

  - Here is a sample using the generic list. Timer1_Timer is very similar to your existing code. I included Timer1_Timer_Rewritten to show you how you can loop through the list with less code:

  'defined by WinForms designer

  Dim picBlue As New PictureBox

  Dim picRed As New PictureBox

  Dim picGreen As New PictureBox

  Dim picWhite As New PictureBox

  'generic List container used to replace the control array

  Dim picBox As New Collections.Generic.List(Of PictureBox)

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

  'Initialize picturebox collection and containing objects

  picBox = New Collections.Generic.List(Of PictureBox)

  For a As Integer = 0 To 150

  picBox.Add(New PictureBox)

  Next

  'assign random images to picboxes

  Me.Timer1_Timer()

  Me.Timer1_Timer_Rewritten()

  End Sub

  Private Sub Timer1_Timer()

  Dim Value As Integer

  Dim a As Integer

  a = 0

  Do While a <= 150

  Randomize()

  Value = Int((4 * Rnd) + 1) ' Generate random value between 1 and 4.

  If Value = 1 Then picBox(a).Image = picBlue.Image

  If Value = 2 Then picBox(a).Image = picRed.Image

  If Value = 3 Then picBox(a).Image = picGreen.Image

  If Value = 4 Then picBox(a).Image = picWhite.Image

  a = a + 1

  Loop

  End Sub

  Private Sub Timer1_Timer_Rewritten()

  For Each picBoxObj As PictureBox In picBox

  Randomize()

  Dim Value As Integer = Int((4 * Rnd()) + 1) ' Generate random value between 1 and 4.

  If Value = 1 Then picBoxObj.Image = picBlue.Image

  If Value = 2 Then picBoxObj.Image = picRed.Image

  If Value = 3 Then picBoxObj.Image = picGreen.Image

  If Value = 4 Then picBoxObj.Image = picWhite.Image

  Next

  End Sub

  
  
• Control Arrays