Xceed DataGrid for WPF v7.2 Documentation
Sorting Data Items

Welcome to Xceed DataGrid, Editors, and 3D Views for WPF v7.2 > Xceed DataGrid for WPF > Code Snippets > Sorting Data Items

The following page provides a list of examples that demonstrate how to sort data items. For more sorting-related information, refer to the Sorting Data topic.

All examples in this topic assume that the grid is bound to the Orders table of the Northwind database, unless stated otherwise.

Sorting data items

The following example demonstrates how to sort the data items in an ascending direction according to the values of the ShipCountry column.

XAML
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<Grid xmlns:scm="clr-namespace:System.ComponentModel;assembly=WindowsBase"
      xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid">
  <Grid.Resources>
    <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"
                                     Source="{Binding Source={x:Static Application.Current},
                                                       Path=Orders}">
     <xcdg:DataGridCollectionViewSource.SortDescriptions>
       <scm:SortDescription PropertyName="ShipCountry" Direction="Ascending"/>
     </xcdg:DataGridCollectionViewSource.SortDescriptions>
    </xcdg:DataGridCollectionViewSource>          
  </Grid.Resources>
  <xcdg:DataGridControl x:Name="OrdersGrid"
                        ItemsSource="{Binding Source={StaticResource cvs_orders}}">
    <xcdg:DataGridControl.Columns>
      <xcdg:Column FieldName="ShipCountry" VisiblePosition="0"/>
    </xcdg:DataGridControl.Columns>
  </xcdg:DataGridControl>
</Grid>
VB.NET
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Dim collectionView As New DataGridCollectionView( Orders )
collectionView.SortDescriptions.Add( New SortDescription( "ShipCountry", ListSortDirection.Ascending ) )
dataGridControl.ItemsSource = collectionView
dataGridControl.Columns( "ShipCountry" ).VisiblePosition = 0
C#
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DataGridCollectionView collectionView = new DataGridCollectionView( Orders );
collectionView.SortDescriptions.Add( new SortDescription( "ShipCountry", ListSortDirection.Ascending ) );
dataGridControl.ItemsSource = collectionView;
dataGridControl.Columns[ "ShipCountry" ].VisiblePosition = 0;

Preventing sorting and grouping

The following example demonstrates how to bind a grid to the Orders table and prevent columns from being sorted and reordered and groups from being created or removed. By default, the ShipCountry and ShipCity columns will be sorted, grouped, and fixed.

XAML
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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"
      xmlns:d="clr-namespace:System.Windows.Data;assembly=PresentationFramework"
      xmlns:scm="clr-namespace:System.ComponentModel;assembly=WindowsBase">
  <Grid.Resources>
    <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"
                                    Source="{Binding Source={x:Static Application.Current},
                                                      Path=Orders}">
      <xcdg:DataGridCollectionViewSource.SortDescriptions>
        <scm:SortDescription PropertyName="ShipCountry" Direction="Ascending"/>
        <scm:SortDescription PropertyName="ShipCity" Direction="Ascending"/>
      </xcdg:DataGridCollectionViewSource.SortDescriptions>
      <xcdg:DataGridCollectionViewSource.GroupDescriptions>
        <xcdg:DataGridGroupDescription PropertyName="ShipCountry"/>
        <xcdg:DataGridGroupDescription PropertyName="ShipCity"/>
      </xcdg:DataGridCollectionViewSource.GroupDescriptions>
    </xcdg:DataGridCollectionViewSource>
  </Grid.Resources>
  <xcdg:DataGridControl x:Name="OrdersGrid"
                        ItemsSource="{Binding Source={StaticResource cvs_orders}}">      
    <xcdg:DataGridControl.Columns>
      <xcdg:Column FieldName="ShipCountry" VisiblePosition="0"/>
      <xcdg:Column FieldName="ShipCity" VisiblePosition="1"/>
    </xcdg:DataGridControl.Columns>
    <xcdg:DataGridControl.View>
      <xcdg:TableView FixedColumnCount="2" UseDefaultHeadersFooters="False">
        <xcdg:TableView.FixedHeaders>
          <DataTemplate>
            <xcdg:GroupByControl AllowSort="False" AllowGroupingModification="False"/>
          </DataTemplate>
          <DataTemplate>
            <xcdg:ColumnManagerRow AllowSort="False" AllowColumnReorder="False"/>
          </DataTemplate>
        </xcdg:TableView.FixedHeaders>
      </xcdg:TableView>
    </xcdg:DataGridControl.View>
  </xcdg:DataGridControl>
</Grid>

Custom sorting

This example demonstrates how to create a custom group description by deriving from the DataGridGroupDescription class and overriding the GroupNameFromItem method. The custom group description will group items according to the first letter in the value received as a parameter. The example results in the group being present at initial loading; also, when removing and re-adding the group, the custom group description is not triggered. See below for an alternative approach to avoid this. 

The implementation for the custom sort comparer assigned to the group description's SortComparer property is provided below.

VB.NET
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Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Xceed.Wpf.DataGrid
Imports System.Collections
Imports System.Globalization;
Namespace Xceed.Wpf.Documentation
  Public Class AlphabeticalGroupDescription
         Inherits DataGridGroupDescription
    Public Sub New()
      MyBase.New()
    End Sub
    Public Sub New(ByVal propertyName As String)
     MyBase.New(propertyName)
    End Sub
    Public Overrides Function GroupNameFromItem(ByVal item As Object, _
                                                ByVal level As Integer, _
                                                ByVal culture As CultureInfo) As Object
      Dim value As Object = MyBase.GroupNameFromItem(item, level, culture)
      Try
        Dim content As String = Convert.ToString(value)
        value = content.ToUpper().Substring(0, 1)
      Catch e1 As InvalidCastException
      End Try
      Return value
    End Function
  End Class
End Namespace
C#
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using System;
using System.Collections.Generic;
using System.Text;
using Xceed.Wpf.DataGrid;
using System.Collections;
namespace Xceed.Wpf.Documentation
{
  public class AlphabeticalGroupDescription : DataGridGroupDescription
  {
    public AlphabeticalGroupDescription()
      : base()
    {
    }
    public AlphabeticalGroupDescription( string propertyName )
      : base( propertyName )
    {
    }
  
    public override object GroupNameFromItem( object item, int level,
                                              System.Globalization.CultureInfo culture )
    {
      object value = base.GroupNameFromItem( item, level, culture );
      try
      {
        string content = Convert.ToString( value );
        value = content.ToUpper().Substring( 0, 1 );
      }
      catch( InvalidCastException )
      {
      }
      return value;
    }
  }
}

The following code demonstrates how to use the custom group description by adding it to the DataGridCollectionViewSource's GroupDescriptions property.

XAML
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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"
     xmlns:local="clr-namespace:Xceed.Wpf.Documentation">
  <Grid.Resources>     
    <local:ConsonantVowelComparer x:Key="consonantVowelComparer"/>
    <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"
                                       Source="{Binding
                                                Source={x:Static Application.Current},
                                                Path=Orders}">
     <xcdg:DataGridCollectionViewSource.GroupDescriptions>
       <local:AlphabeticalGroupDescription PropertyName="ShipCountry"
                                SortComparer="{StaticResource consonantVowelComparer}"/>
     </xcdg:DataGridCollectionViewSource.GroupDescriptions>
    </xcdg:DataGridCollectionViewSource>
  </Grid.Resources>
  <xcdg:DataGridControl x:Name="OrdersGrid"
                        ItemsSource="{Binding Source={StaticResource cvs_orders}}"/>
</Grid>
VB.NET
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Dim collectionView As New DataGridCollectionView( Orders )
Dim groupDescription As New AlphabeticalGroupDescription( "ShipCountry" )
groupDescription.SortComparer = New ConsonantVowelComparer()
collectionView.GroupDescriptions.Add( groupDescription )
dataGridControl.ItemsSource = collectionView
C#
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DataGridCollectionView collectionView = new DataGridCollectionView( Orders );
AlphabeticalGroupDescription groupDescription = new AlphabeticalGroupDescription( "ShipCountry" );
groupDescription.SortComparer = new ConsonantVowelComparer();
collectionView.GroupDescriptions.Add( groupDescription );
dataGridControl.ItemsSource = collectionView;

The following code provides the implementation for the custom sort comparer that is used to sort, by vowels then consonants, the group descriptions create above.

VB.NET
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Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Collections
Namespace Xceed.Wpf.Documentation
  Public Class ConsonantVowelComparer
     Implements IComparer
    Public Sub New()
    End Sub

    Public Function Compare(ByVal x As Object, _
                            ByVal y As Object) As Integer Implements IComparer.Compare
      If (TypeOf x Is String) AndAlso (TypeOf y Is String) Then
        Dim xString As String = x.ToString().ToLowerInvariant()
        Dim yString As String = y.ToString().ToLowerInvariant()
        Dim isXVowel As Boolean = m_vowels.Contains(xString)
        Dim isYVowel As Boolean = m_vowels.Contains(yString)
        If isXVowel Xor isYVowel Then
          If isXVowel Then
            Return -1
          Else
            Return 1
          End If
        End If
        Return String.Compare(xString, yString)
      End If
      Throw New ArgumentException()
    End Function
    Private Const m_vowels As String = "aeiouy"
  End Class
End Namespace
C#
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using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace Xceed.Wpf.Documentation
{
  public class ConsonantVowelComparer : IComparer
  {
    public ConsonantVowelComparer()
    {
    }
    public int Compare( object x, object y )
    {
      if( ( x is string ) && ( y is string ) )
      {
        string xString = x.ToString().ToLowerInvariant();
        string yString = y.ToString().ToLowerInvariant();
        bool isXVowel = m_vowels.Contains( xString );
        bool isYVowel = m_vowels.Contains( yString );
        if( isXVowel ^ isYVowel )
          return isXVowel ? -1 : 1;
        return String.Compare( xString, yString );      
      }
      throw new ArgumentException();
    }
    private const string m_vowels = "aeiouy";
  }
}

The first example results in the group being present at initial loading; also, when removing and re-adding the group, the custom GroupDescription is not triggered. But by adding the custom GroupDescription directly to the Column, data is not grouped until the end-user drags the column to create the group.

<Window.Resources>
    <local:DateGroupDescription x:Key="myDateGroupDescription"
                                PropertyName="DateTimeFieldName" />
</Window.Resources>

[...]

<xcdg:DataGridControl.Columns>
  <xcdg:Column FieldName="DateTimeFieldName"
              GroupDescription="{StaticResource myDateGroupDescription}" />
</xcdg:DataGridControl.Columns>

 

Handling collection-changed events

The following example demonstrates how to subscribe to the CollectionChanged event of the DataGridCollectionView.SortDescriptions collection's INotifyCollectionChanged interface implementation to be notified when sorting applied to a grid's columns changes.

VB.NET
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Protected Overrides Sub OnInitialized(ByVal e As EventArgs)
  MyBase.OnInitialized(e)

  Dim view As DataGridCollectionView = TryCast(Me.OrdersGrid.ItemsSource, DataGridCollectionView)
  AddHandler (CType(view.SortDescriptions, INotifyCollectionChanged)).CollectionChanged,
                                           AddressOf SortCollectionChanged
End Sub
Private Sub SortCollectionChanged(ByVal sender As Object, ByVal e As NotifyCollectionChangedEventArgs)
  Debug.WriteLine("Sort changed")
End Sub
C#
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protected override void OnInitialized( EventArgs e )
{
  base.OnInitialized( e ); 
  DataGridCollectionView view = this.OrdersGrid.ItemsSource as DataGridCollectionView;
  ( ( INotifyCollectionChanged )view.SortDescriptions ).CollectionChanged +=
                                      new NotifyCollectionChangedEventHandler( this.SortCollectionChanged );
} 
private void SortCollectionChanged( object sender, NotifyCollectionChangedEventArgs e )
{
  Debug.WriteLine( "Sort changed" );
}

Providing a custom sort comparer

The following example demonstrates how to provide a custom sort comparer that sorts addresses. The AddressComparer class (provided below) will first sort addresses which begin with numeric values by street name and then civic number. Address that do not have a civic number will be sorted alphabetically.

XAML
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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"
      xmlns:local="clr-namespace:Xceed.Wpf.Documentation">
   <Grid.Resources>
      <local:AddressComparer x:Key="addressComparer"/>
      <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"
                                         Source="{Binding Source={x:Static Application.Current},
                                                          Path=Orders}"
                                         AutoCreateItemProperties="False">
         <xcdg:DataGridCollectionViewSource.ItemProperties>
            <xcdg:DataGridItemProperty Name="ShipCountry" />
            <xcdg:DataGridItemProperty Name="ShipCity" />
            <xcdg:DataGridItemProperty Name="ShipAddress"
                                       SortComparer="{StaticResource addressComparer}"/>
            <xcdg:DataGridItemProperty Name="ShipVia" />
         </xcdg:DataGridCollectionViewSource.ItemProperties>
      </xcdg:DataGridCollectionViewSource>
   </Grid.Resources>
   <xcdg:DataGridControl x:Name="OrdersGrid"
                         ItemsSource="{Binding Source={StaticResource cvs_orders}}"/>         
</Grid>
VB.NET
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Dim collectionView As New DataGridCollectionView( Orders, GetType( System.Data.DataRow ), False, False )
collectionView.ItemProperties.Add( New DataGridItemProperty( "ShipCountry", GetType( String ) ) )
collectionView.ItemProperties.Add( New DataGridItemProperty( "ShipCity", GetType( String ) ) )
collectionView.ItemProperties.Add( New DataGridItemProperty( "ShipVia", GetType( Integer ) ) )
Dim shipAddress As New DataGridItemProperty( "ShipAddress", GetType( String ) )
shipAddress.SortComparer = New AddressComparer()
collectionView.ItemProperties.Add( shipAddress )
dataGridControl.ItemsSource = collectionView
C#
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DataGridCollectionView collectionView = new DataGridCollectionView( Orders, typeof( System.Data.DataRow ), false, false );
collectionView.ItemProperties.Add( new DataGridItemProperty( "ShipCountry", typeof( string ) ) );
collectionView.ItemProperties.Add( new DataGridItemProperty( "ShipCity", typeof( string ) ) );
collectionView.ItemProperties.Add( new DataGridItemProperty( "ShipVia", typeof( int ) ) );
DataGridItemProperty shipAddress = new DataGridItemProperty( "ShipAddress", typeof( string ) );
shipAddress.SortComparer = new AddressComparer();
collectionView.ItemProperties.Add( shipAddress );
dataGridControl.ItemsSource = collectionView;

The following code provides the implementation of the AddressComparer class.

VB.NET
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Imports System
Imports System.Collections
Imports System.Data
Namespace Xceed.Wpf.Documentation
  Public Class AddressComparer
               Implements IComparer
    Public Sub New()
    End Sub
    Public Function Compare( x As Object, y As Object ) As Integer Implements IComparer.Compare
      Dim stringX As String = CType( x, String )
      Dim stringY As String = Ctyle( y, String )
      Const digits As String = "0123456789"
      If( ( digits.IndexOf( stringX( 0 ) ) >= 0 ) And ( digits.IndexOf( stringY( 0 ) ) >= 0 ) ) Then
        Dim index As Integer = 0
        Dim xNumber As System.Text.StringBuilder = New System.Text.StringBuilder()
        While( ( index < stringX.Length ) And ( digits.IndexOf( stringX( index ) ) >= 0 ) )
          xNumber.Append( stringX( index ) )
          index++
        End While
        index = 0
        Dim yNumber As System.Text.StringBuilder = New System.Text.StringBuilder()
        While( ( index < stringY.Length ) And ( digits.IndexOf( stringY( index ) ) >= 0 ) )
          yNumber.Append( stringY( index ) )
          index++
        End While
        Dim xValue = Long.Parse( xNumber.ToString() )
        Dim yValue As Long = Long.Parse( yNumber.ToString() )
        If( xValue > yValue ) Then
          Return 1
        End If
        If( xValue < yValue ) Then
          Return -1
        End If
        Return stringX.CompareTo( stringY )
      Else
        Return stringX.CompareTo( stringY )
      End If
    End Function
  End Class
End Namespace
C#
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using System;
using System.Collections;
using System.Data;
namespace Xceed.Wpf.Documentation
{
 public class AddressComparer: IComparer
 {
   public AddressComparer()
   {
   }
   int IComparer.Compare( object x, object y )
   {
     string stringX = ( string )x;
     string stringY = ( string )y;
     const string digits = "0123456789";
     if( ( digits.IndexOf( stringX[ 0 ] ) >= 0 ) && ( digits.IndexOf( stringY[ 0 ] ) >= 0 ) )
     {
       int index = 0;
       System.Text.StringBuilder xNumber = new System.Text.StringBuilder();
       while( ( index < stringX.Length ) && ( digits.IndexOf( stringX[ index ] ) >= 0 ) )
       {
         xNumber.Append( stringX[ index ] );
         index++;
       }
       index = 0;
       System.Text.StringBuilder yNumber = new System.Text.StringBuilder();
       while( ( index < stringY.Length ) && ( digits.IndexOf( stringY[ index ] ) >= 0 ) )
       {
         yNumber.Append( stringY[ index ] );
         index++;
       }
       long xValue = long.Parse( xNumber.ToString() );
       long yValue = long.Parse( yNumber.ToString() );
       if( xValue > yValue )
         return 1;
       if( xValue < yValue )
         return -1;
       return stringX.CompareTo( stringY );
     }
     else
     {
       return stringX.CompareTo( stringY );
     }
   }
 }
}