Collections

Question

Hi all. I am trying to make use of a collections that simultaneously changes a property of several objects. Here is what I've crafted so far:  Private Sub Button1_Click(ByVal sender etc etc...) Dim cmbBoxCollection As New Collection With cmbBoxCollection .Add(ComboBox1.Enabled) .Add(ComboBox2.Enabled) .Add(ComboBox3.Enabled) End With Dim IndexValue As Integer For Each IndexValue In cmbBoxCollection Enabled = False Next  However when I run the application pressing the button sets everything on the form to enabled=false. If I go for the Visible=False option the whole form dissapears. What could be the problem? Thx in advance

mibuyt · Answer

Hi I had converted into VB.NET ControlContainer.vb ------------------------- Imports System.Collections Imports System.Windows.Forms Public Class ControlContainer Implements IEnumerable Private controlList As ArrayList Public Sub New() controlList = New ArrayList End Sub Public Sub AddControl(ByVal ctrl As Control) controlList.Add(ctrl) End Sub Public Function GetEnumerator() As System.Collections.IEnumerator Implements System.Collections.IEnumerable.GetEnumerator Return controlList.GetEnumerator() End Function End Class Form1.vb ------------ Private Sub Button1_Click(ByVal sender As System.Object ByVal e As System.EventArgs) Handles Button1.Click Dim cCon As ControlContainer cCon = New ControlContainer With cCon .AddControl(TextBox1) .AddControl(Label1) End With Dim ctrl As Control For Each ctrl In cCon ctrl.Visible = False Next End Sub The benefits of using this is that you set visible=false to all the windows forms control instead of just combobox. Cheers.

mibuyt · Answer

Hi Noted. I will figure it out in VB.NET then. Cheers.

MythicalMe · Answer

If you can't code in VB.Net why are you posting solutions in the VB.Net forum? I understand your exuberance to help people with their problems but answers in this forum need to be written in VB.NET. Thanks

mibuyt · Answer

Hi Half Yeah.. well i can't code vb.net. So i only can help in giving C# solution. Cheers.

orkael · Answer

Thanks a lot MythicalMe. Seems I had gotten the logic all wrong. Chua Wen Ching I was trying to figure out the vb way but I am sure your implementation works fine as well:) Regards

mibuyt · Answer

Hi This is how i achieve it and yes it is working entirely fine. public class ControlContainer : IEnumerable { private ArrayList controlList; public ControlContainer() { controlList = new ArrayList(); } public void AddControl(System.Windows.Forms.Control ctrl) { controlList.Add(ctrl); } public IEnumerator GetEnumerator() { return controlList.GetEnumerator(); } } private void button2_Click(object sender System.EventArgs e) { ControlContainer cCon = new ControlContainer(); cCon.AddControl(textBox1); cCon.AddControl(label1); cCon.AddControl(button1); foreach (Control ctrl in cCon) { ctrl.Visible = false; } } Hope you find it useful. Cheers.

MythicalMe · Answer

A collection is simply a container to put things. In cmbBoxCollection you're placing a bunch of boolean values. That won't work. You'll have to place the entire combobox in the collection then iterate through. Further you've used FOR EACH wrong. Your collection was a collection of boolean values not integer. Finally when you used VISIBLE = FALSE the compiler took that to mean: ME.Visible = FALSE ME being the form. Correctly: Dim cmbBoxCollection as New Collection With cmbBoxCollection .Add(ComboBox1) .Add(ComboBox2) .Add(ComboBox3) End WIth dim cmbBox as comboBox For Each cmbBox in cmbBoxCollection cmbBox.Visible = FALSE Next

orkael · Answer

Ok what i mean is that I want to use a collection in order to mass change a property of several objects on the form by clicking a button. Unfortunately when i click the button not just the property of the objects included in the collection change but the property of all the objects on the form (including the porperty of the form itself) change. By If I go for the Visible=False option I mean when I create a collection in order to change the property Visible of objects inlcuding in the collection not only these objects become invisible but all the objects on the form (including the form itself) become invisible:  Private Sub Button1_Click(ByVal sender etc etc...) Dim cmbBoxCollection As New Collection With cmbBoxCollection .Add(ComboBox1.Visible) .Add(ComboBox2.Visible) .Add(ComboBox3.Visible) End With Dim IndexValue As Integer For Each IndexValue In cmbBoxCollection Visible = False Next  Regards

mibuyt · Answer

Hi Do you mind to elaborate more on this? If I go for the Visible=False option the whole form dissapears. I am a bit confuse but I hope i can help you somehow. Cheers.