ComponentOne FlexGrid for WPF and Silverlight
GroupHeaderConverter Property (C1FlexGrid)
Example 

C1.WPF.FlexGrid Namespace > C1FlexGrid Class : GroupHeaderConverter Property
Gets or sets the System.Windows.Data.IValueConverter used to create the content shown in GroupRow cells to summarize group information.
Syntax
'Declaration
 
Public Property GroupHeaderConverter As System.Windows.Data.IValueConverter
public System.Windows.Data.IValueConverter GroupHeaderConverter {get; set;}
Remarks

By default, the grid creates group headers that show the name of the property being grouped on, the value of the property, and the number of items in the group.

You can modify or customize this information by defining your own group header converter class and assigning an instance of this class to the grid's GroupHeaderConverter property.

Example
The example below shows the default group header converter class implementation.
class GroupHeaderConverter : IValueConverter
{
  public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
  {
    var gr = parameter as GroupRow;
    var group = gr.Group;
    if (group != null && gr != null && targetType == typeof(string))
    {
      var desc = gr.Grid.CollectionView.GroupDescriptions[gr.Level] as PropertyGroupDescription;
      return desc != null
        ? string.Format("{0}: {1} ({2:n0} item{3})", 
            desc.PropertyName, 
            group.Name, 
            group.ItemCount, 
            group.ItemCount == 1 ? string.Empty : "s")
        : string.Format("{0} ({1:n0} items)", group.Name, group.ItemCount);
    }
      
    // default
    return value;
  }
  public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
  {
    return value;
  }
}
See Also

Reference

C1FlexGrid Class
C1FlexGrid Members