how to create control array ? in vb .net

Tom Deketelaere

what do you mean exactly. from what I understand you could do it with the list variable. example: dim l as list (of button) dim l as list (of textbox) dim l as lizt (of control) (don't know how/if this will work though)

babusat

exactly i want create control array like vb like example: textbox(0) in runtime or at design time sathish

Tom Deketelaere

Then I would use the list example code that creates a list and fills it with 20 textbox Private l As New List(Of TextBox) Private Sub filltextbox() Dim i As Integer = 0 Do While i < 20 Dim txt As New TextBox txt.Text = "test" + i l.Add(txt) i += 1 Loop End Sub

babusat

it is very useful but i want to access textbox values using there index value and in this the textbox names are different why ? sathish

Tom Deketelaere

don't really know what you mean the textbox names aren't different I just added text to it as a way to show how to access te property's If you want to access the textbox with index value you could always give that index value along with the textbox.tag property and then loop true the list untill you find the right textbox

TwoFaced

There is no design time support for creating control arrays. Here is some code that demonstrates a few different approaches.

Public Class Form1
' An array of textbox's
Private ControlArray As New List(Of TextBox)

Private Sub Form1\_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    ' Here I am adding TextBox's that already exist on my form to the array
    With ControlArray
        .Add(TextBox1)
        .Add(TextBox2)
        .Add(TextBox3)
    End With

    ' Loop through each textbox in the array
    For Each tb As TextBox In ControlArray
        MsgBox(tb.Name)
    Next

    ' Access a textbox by index
    MsgBox(ControlArray(1).Name)

    ' Here I am creating textboxes dynamically and adding them
    ' to the array
    For i As Integer = 0 To 2
        ' Create a textbox
        Dim tb As New TextBox
        ' Set it's position
        tb.Location = New Point(20, 10 + i \* 30)
        ' Set it's width
        tb.Width = 100

        ' Add the textbox to the array
        ControlArray.Add(tb)

        ' Add the textbox to the form
        Me.Controls.Add(tb)

        ' Add handlers for the GotFocus and LostFocus events
        AddHandler tb.GotFocus, AddressOf TextBox\_GotFocus
        AddHandler tb.LostFocus, AddressOf TextBox\_LostFocus
    Next

    ' Here I've looped through the forms controls and found
    ' all the textboxes and added them to the array
    ' This is a good approach if you have many controls you added at
    ' design time but don't want to manually add each one to the array.
    ' The desired event handlers can also be dynamically added this way
    For Each ctrl As Control In Me.Controls
        Dim tb As TextBox = TryCast(ctrl, TextBox)
        If tb IsNot Nothing Then
            ControlArray.Add(tb)
        End If
    Next
End Sub

' Handles the textboxes GotFocus event
' I've handled the controls I created at design time by including them after the handles keyword
Private Sub TextBox\_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.GotFocus, TextBox2.GotFocus, TextBox3.GotFocus
    ' tb is a reference to the textbox that raised this event
    Dim tb As TextBox = DirectCast(sender, TextBox)
    tb.BackColor = Color.Wheat
End Sub

' Handles the textboxe

babusat

thanks for your help and another thing that i want to known textbox name which currently active. i could not get it name from MsgBox(Me.ActiveControl.Name) this command why ? thanks sathish

TwoFaced

Me.ActiveControl will give you a reference to the control that has focus. The problem I'm guessing is your code resides in a button click event. If you click the button it gets focus so Me.ActiveControl.Name will return the buttons name. What exactly are you trying to do? Can you describe the program a little?

babusat

the problem is Me.ActiveControl.Name does not display any name that's only i asked why ? and i want to known which textbox is currently active thank you sathish

TwoFaced

I showed you code to dymanically create textboxs, is that how these textbox's were created or were they created at design time? Controls created at design time are given a default name, however, controls created at runtime are not. When you create the textbox you need to set it's name property. This is one reason why 'Name' may not be returning anything.