Labels' Click events - vb.net

Question

I have an application where I have around 50 labels. In those labels a number is visible.
When the user clicks on the label the number needs to be written to an edit box.
This works fine, the only problem is that I have added 50 functions like below, and every time it’s the same. I was wondering if there is a common function for this
Remark: The labels have different names. So if its possible that this will work for all the labels on the form.
Private Sub LI_L_Click(sender As Object, e As EventArgs) Handles LI_L.Click
cmbOBJID.Text = LI_L.Text
End Sub

Answer 1

In the form designer, you should be able to set the handler for every label to the same function. Then you can use the "sender" parameter to determine which label is raising the event.
Notice also how all the controls that the function is linked to are listed after the "Handles" keyword. This is another way you could connect the code to all the labels if you prefer this over using the Visual Studio UI properties grid.
Private Sub LI_Click(sender As Object, e As EventArgs) Handles Label1.Click, Label2.Click, Label3.Click
cmdOBJID.Text = DirectCast(sender, Label).Text
End Sub

Answer 2

While it is easy to add several events to one handler in the style of
Private Sub LI_Click(sender As Object, e As EventArgs) Handles Label1.Click, Label2.Click, Label3.Click
It will be tedious for more than just a few labels.
You can add handlers programatically if you can find a way to refer to the labels you need to add handlers to. In this example, I put all the labels in a groupbox named "GroupBoxOptions":
Option Infer On
Option Strict On
Public Class Form1
Sub TransferDataToEditBox(sender As Object, e As EventArgs)
Dim lbl = DirectCast(sender, Label)
tbEditThis.Text = lbl.Text
End Sub
Sub InitLabelHandlers()
For Each lbl In GroupBoxOptions.Controls.OfType(Of Label)
AddHandler lbl.Click, AddressOf TransferDataToEditBox
Next
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
InitLabelHandlers()
End Sub
End Class
You may have some other way of selecting the labels which use the handler.

Answer 3

A pretty nice and quick solution is to traverse all the label controls on a form, assigning through the AddHandler function the event to run when a user clicks a label.
In code:
For Each c As Control In Me.Controls.OfType(Of Label)
AddHandler c.Click, AddressOf myLabelClick
Next
With the prevous snippet, we loop onto all the winform controls of type Label. A loop like that is useful when we have a lot of labels for which an event must be assigned. For each of them, we associate the event Click of the control with a customized Sub named myLabelClick. That subroutine will look like the following:
Private Sub myLabelClick(sender As Object, e As EventArgs)
cmdObjId.Text = DirectCast(sender, Label).Text
End Sub
Here we use the sender variable (which represents the control for which the click has been done) to access its Text property, and change the cmdObjId.Text accordingly.

Answer 4

Just to complement the solution from BlueMonkMN:
If you are using the DevExpress Tools, you need to import DevExpress.XtraEditors and change Label to LabelControl:
DirectCast(sender, LabelControl).Text
This worked for me.