/// <summary>
/// Convert a TreeViewItem into a value based on the depth of the item
/// in the TreeView.
/// </summary>
/// <param name="value">The TreeViewItem.</param>
/// <param name="targetType">
/// The indentation type to convert to (such as Thickness or double).
/// </param>
/// <param name="parameter">
/// The number of pixels to indent each level of the TreeView. A
/// default value of 15.0 will be used if no parameter is provided.
/// </param>
/// <param name="culture">
/// The culture used to convert the TreeViewItem.
/// </param>
/// <returns>
/// A value based on the depth of the item in the TreeView.
/// </returns>
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
TreeViewItem item = value as TreeViewItem;
if (item != null)
{
// Determine the number of pixels to indent each level of the
// TreeView (or use the default value of 15.0)
double indentationPerDepth = 15.0;
string indentationPerDepthParameter = parameter as string;
if (string.IsNullOrEmpty(indentationPerDepthParameter) ||
double.TryParse(indentationPerDepthParameter, NumberStyles.Any, culture, out indentationPerDepth))
{
try
{
// Convert the depth into the indentation
double indentation = item.GetDepth() * indentationPerDepth;
return(WrapIndentation(indentation, targetType));
}
catch (ArgumentException)
{
// Ignore the case where a TreeViewItem isn't associated
// with a TreeViewItem, in which case we'll return an
// indentation of zero anyway
}
}
}
return(WrapIndentation(0, targetType));
}