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ComboBox.DropDownOpened Event

  • Reference

Definition

Namespace:
System.Windows.Controls
Assembly:
PresentationFramework.dll

Occurs when the drop-down list of the combo box opens.

public:
 event EventHandler ^ DropDownOpened;
public event EventHandler DropDownOpened;
member this.DropDownOpened : EventHandler 
Public Custom Event DropDownOpened As EventHandler

Event Type

EventHandler

Examples

The following example shows how to assign event handlers and handle the DropDownOpened and DropDownClosed events.

<ComboBox Name="cb" StaysOpenOnEdit="true" IsEditable="true" DropDownOpened="OnDropDownOpened" 
        DropDownClosed="OnDropDownClosed">

void OnDropDownOpened(object sender, EventArgs e)
{
    if (cb.IsDropDownOpen)
    {
        cb.Text = "Combo box opened";
    }
}

void OnDropDownClosed(object sender, EventArgs e)
{
    if (!cb.IsDropDownOpen)
    {
        cb.Text = "Combo box closed";
    }
}

Private Sub OnDropDownOpened(ByVal Sender As Object, ByVal e As EventArgs)

    If (cb.IsDropDownOpen = True) Then
        cb.Text = "Combo box opened"
    End If

End Sub

Private Sub OnDropDownClosed(ByVal Sender As Object, ByVal e As EventArgs)

    If (cb.IsDropDownOpen = False) Then
        cb.Text = "Combo box closed"
    End If

End Sub

Applies to