Filter Modes and Custom Filtering

• Aug 23, 2018
• 3 minutes to read

Note

Filtering by display text and custom filtering are not supported in server mode.

Filter Modes

The grid allows its data to be filtered by column values (edit values) or display text. Use the ColumnBase.ColumnFilterMode property to specify the column’s filter mode.

• Filter by Column Values

  Set the ColumnBase.ColumnFilterMode property to ColumnFilterMode.Value.

  

• Filter by Display Text

  Set the ColumnBase.ColumnFilterMode property to ColumnFilterMode.DisplayText. End-users must enter text that matches the column’s formatted value(s) completely.

  

Custom Filtering

Custom filtering is hiding particular rows that exist in a data source, or making them visible. Custom filtering takes priority over filter criteria applied using a column’s filter dropdown or using the Automatic Filter Row.

To manually filter data rows, handle the GridControl.CustomRowFilter event. This event is raised for each record in a data source. The currently processed record is identified by its index in a data source, returned by the event parameter’s ListSourceRowIndex property. To identify the row which corresponds to the processed record, use the GridControl.GetRowHandleByListIndex method.

To hide or show a row, specify the event parameter’s Visible property and set the Handled property to true. If the Handled parameter is set to false, the record’s visibility is determined by the filter currently applied to a View. So, the record will only be visible if it matches the View’s filter. Otherwise, it will be hidden.

Example

This example demonstrates how to implement custom filtering in the DXGrid control.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-implement-custom-filtering-e1167.

Window1.xaml

<Window x:Class="CustomFiltering.Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
        Title="Window1" Height="300" Width="300">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="36" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <StackPanel Grid.Row="0" Orientation="Horizontal">
            <CheckBox Name="chkHideEven" Margin="7,0,7,0" VerticalAlignment="Center" 
                      Content="Hide Even Rows"
                      Checked="chk_CheckedOrUnchecked"
                      Unchecked="chk_CheckedOrUnchecked" />
            <CheckBox Name="chkHideOdd" VerticalAlignment="Center" Content="Hide Odd Rows"
                      Checked="chk_CheckedOrUnchecked" Unchecked="chk_CheckedOrUnchecked" />
        </StackPanel>
        <dxg:GridControl Name="grid" Grid.Row="1" AutoGenerateColumns="AddNew" CustomRowFilter="grid_CustomRowFilter">
            <dxg:GridControl.View>
                <dxg:TableView Name="view" AutoWidth="True" ShowGroupPanel="False" NavigationStyle="None" />
            </dxg:GridControl.View>
        </dxg:GridControl>
    </Grid>
</Window>

Window1.xaml.cs

using System.Windows;
using DevExpress.Xpf.Grid;

namespace CustomFiltering {

    public partial class Window1 : Window {

        public Window1() {
            InitializeComponent();
            grid.ItemsSource = new object[] { "A", "B", "C", "D", "E", "F", "G", "H" };
        }

        private void grid_CustomRowFilter(object sender, RowFilterEventArgs e) {
            if (chkHideOdd.IsChecked.Value && e.ListSourceRowIndex % 2 == 1)
                e.Visible = false;
            if (chkHideEven.IsChecked.Value && e.ListSourceRowIndex % 2 == 0)
                e.Visible = false;
            e.Handled = !e.Visible ? true : false;
        }

        private void chk_CheckedOrUnchecked(object sender, RoutedEventArgs e) {
            grid.RefreshData();
        }
    }
}

Window1.xaml.vb

Imports System.Windows
Imports DevExpress.Xpf.Grid

Namespace CustomFiltering

    Partial Public Class Window1
        Inherits Window

        Public Sub New()
            InitializeComponent()
            grid.ItemsSource = New Object() { "A", "B", "C", "D", "E", "F", "G", "H" }
        End Sub

        Private Sub grid_CustomRowFilter(ByVal sender As Object, ByVal e As RowFilterEventArgs)
            If chkHideOdd.IsChecked.Value AndAlso e.ListSourceRowIndex Mod 2 = 1 Then
                e.Visible = False
            End If
            If chkHideEven.IsChecked.Value AndAlso e.ListSourceRowIndex Mod 2 = 0 Then
                e.Visible = False
            End If
            e.Handled = If((Not e.Visible), True, False)
        End Sub

        Private Sub chk_CheckedOrUnchecked(ByVal sender As Object, ByVal e As RoutedEventArgs)
            grid.RefreshData()
        End Sub
    End Class
End Namespace