# Expandability

Expander is an expandable and collapsible information panel whose expandability can be controlled. Learn more about it's expandability in Expander for WPF documentation.

## Content

By default, you can expand the content area of the Expander control by simply clicking on the header bar as [IsExpandable](/componentone/api/wpf/online-accordion5/dotnet-api/C1.WPF.Accordion/C1.WPF.Accordion.C1Expander.IsExpandable.html) property of the Expander control is set to **True**. However, there might be a scenario where you may want to prevent expansion of the Expander control until a specific event occurs. In that case, you would need to set **IsExpandable** property to **False** as you want the Expander control to remain collapsed until the occurrence of the specified event.

The following code showcases the use of the IsExpandable property. In this example, the IsExpandable property is set to false to keep the Expander control in collapsed state.

```xml
<c1:C1Expander x:Name="ExpanderControl" Header="Expand Me!" IsExpandable="False" FontFamily="Cambria" FontWeight="Bold" VerticalAlignment="Center" HorizontalAlignment="Center">
        <CheckBox Margin="10" VerticalAlignment="Center" x:Name="Condition" Content="CheckBox Inside Expander"/>
</c1:C1Expander>
```

```csharp
ExpanderControl.IsExpandable = false;
```