Control.ControlCollection.Add Method (Control)


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Adds the specified control to the control collection.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public Overridable Sub Add (
	value As Control


Type: System.Windows.Forms.Control

The Control to add to the control collection.

Exception Condition

The specified control is a top-level control, or a circular control reference would result if this control were added to the control collection.


The object assigned to the value parameter is not a Control.

The Add method allows you to add Control objects to the end of the control collection.

You can also add new Control objects to the collection by using the AddRange method.

To remove a Control that you previously added, use the Remove, RemoveAt, or Clear methods.


A Control can only be assigned to one Control.ControlCollection at a time. If the Control is already a child of another control it is removed from that control before it is added to another control.

Notes to Inheritors:

When overriding Add in a derived class, be sure to call the base class's Add method to ensure that the control is added to the collection.

The following code example adds a Control to the Control.ControlCollection of the derived class Panel. The example requires that you have created a Panel control and a Button control on a Form. When the button is clicked, a TextBox control is added to the panel's Control.ControlCollection.

  ' Create a TextBox to add to the Panel.
  Dim TextBox1 As TextBox = New TextBox()

  ' Add controls to the Panel using the Add method.
  Private Sub AddButton_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles AddButton.Click
  End Sub

.NET Framework
Available since 1.1
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