Column Class
See Also  Members   Example 
Xceed.Wpf.DataGrid Assembly > Xceed.Wpf.DataGrid Namespace : Column Class

Represents a column, which defines information on how the Cells it contains are displayed and their content edited.

Object Model






Syntax

Visual Basic (Declaration) 
Public Class Column 
   Inherits DependencyObject
   Implements INotifyPropertyChanged 
C# 
public class Column : DependencyObject, INotifyPropertyChanged 

Example

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

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.
XAMLCopy Code
<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}}">          
      <xcdg:DataGridControl.View> 
         <xcdg:TableView ColumnStretchMode="StretchAll"/> 
      </xcdg:DataGridControl.View> 
   </xcdg:DataGridControl> 
</Grid>
The following code provides the implementation of the AddressComparer class.
Visual BasicCopy Code
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
The following code provides the implementation of the AddressComparer class.
C#Copy Code
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 );
    }
  }
}
}

Remarks

The VisiblePosition property represents the visible position of the column in a grid and may, or may not, correspond to the Index property. A column's visible position can be regarded as the position the column will take when it is visible. Changing a column's visibility will not affect its visible position, allowing the visibility of columns to be changed without them being reordered. To retrieve the effective visible position of a column, the IndexOf method of the VisibleColumns collection can be used.

When fixing columns in a table-view layout, columns will be fixed in the order represented by their VisiblePosition properties. For example, if the FixedColumnCount property is set to 2, then the columns whose VisiblePosition properties are 0 and 1 will be fixed.

If a grid contains hidden columns, they will be ignored. For example, if the second and third columns are hidden and a fixed-column count of 2 is provided, the first and fourth columns will be fixed but their visible positions will not be modified to reflect their new positions. This feature is available only in the Professional Edition

Inheritance Hierarchy

System.Object
   System.Windows.Threading.DispatcherObject
      System.Windows.DependencyObject
         Xceed.Wpf.DataGrid.Column

Requirements

Supported Operating Systems: Windows Server 2003 Service Pack 1; Windows Vista; Windows XP Service Pack 2

See Also