Question

Imagine you have buttons and everytime you click on one,it writes a text to a textbox.

ie:

   Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button41.Click
        textbox.Text &= "1"
    End Sub

And lets say you have 10 of these buttons as numbers (0-9 for example.)Instead of handling the click events of these buttons one by one (buttonxclickevent handles textbox.text = x for example);is there a more elegant way to iterate throught these buttons and events?

Answer 1

Since you have shown VB.NET code, i’ll answer with VB.NET. You could use one handler for all:

Public Class Form1

    Private Sub Form1_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        For Each btn In Me.Controls.OfType(Of Button)()
            AddHandler btn.Click, AddressOf buttonClicked
        Next
    End Sub

    Private Sub buttonClicked(sender As Object, e As EventArgs)
        Dim btn As Button = DirectCast(sender, Button)
        TextBox1.Text &= "1"
    End Sub

End Class

Enumerable.OfType filters and casts, so the result is an IEnumerable(Of Button).