Xceed Logo
Shop
Xceed Toolkit Plus for WPF v5.1 Documentation
Xceed.Wpf.ListBox Assembly / Xceed.Wpf.Data Namespace / OrFilterExpression Class
Example


In This Topic
    OrFilterExpression Class
    In This Topic
    Represents a logical OR filter expression, which states that an item must match one of the specified child filters in order to be included.
    Object Model
    OrFilterExpression ClassFilterExpressionCollection ClassFilterExpressionBase Class
    Syntax
    'Declaration
 

    <DebuggerDisplayAttribute("FilterBy = {DebuggerDisplayString}")>
<ContentPropertyAttribute("ChildExpressions")>
Public NotInheritable Class OrFilterExpression 
   Inherits FilterExpressionOperator
    'Usage
 

    Dim instance As OrFilterExpression
    [DebuggerDisplay("FilterBy = {DebuggerDisplayString}")]
[ContentProperty("ChildExpressions")]
public sealed class OrFilterExpression : FilterExpressionOperator
    Remarks
    Once the filter expression has been created, it is considered "frozen" and its values can no longer be modified.
    Example
    <sldg:DataGridControl x:Name="sldgDataGridControl"
                      ItemsSource="{Binding Path=Orders}">
    <sldg:DataGridControl.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <sldg:SignatureThemeResourceDictionary />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </sldg:DataGridControl.Resources>
    
    <sldg:DataGridControl.FixedHeaders>
        <CheckBox Content="Display only French-Speaking Countries"
                  Checked="CheckBox_Checked"
                  Unchecked="CheckBox_Unchecked"
                  Style="{StaticResource SignatureThemeCheckBoxStyle}"/>
        <sldg:FilterRow>
            <sldg:FilterRow.FilterExpression>
                <sldg:AndFilterExpression>
                    <sldg:FilterExpression MemberName="ShipVia"
                                           Value="3"
                                           FilterOperator="Equal" />
                    <sldg:FilterExpression MemberName="OrderDate"
                                           Value="2008/01/01"
                                           FilterOperator="GreaterThanOrEqual"
                                           IsTimeSensitive="False"/>                            
                </sldg:AndFilterExpression>
            </sldg:FilterRow.FilterExpression>
        </sldg:FilterRow>
    </sldg:DataGridControl.FixedHeaders>
</sldg:DataGridControl>
    Private m_frenchCountries As New List( Of String)( New String( 27 )
       { "Belgium", "Benin", "Burkina-Faso", "Burundi", 
         "Cameroon", "Canada", "Central African Republic", "Chad", "Comoros", 
         "Congo", "Djibouti", "France", "Gabon", "Guinea", "Haiti", "Ivory Coast", 
         "Luxembourg", "Madagascar", "Mali", "Monaco", "Niger", "Rwanda", 
         "Senegal", "Seychelles", "Switzerland", "Togo", "Vanuatu" } ) 

Private Function CreateFilterExpression() As OrFilterExpression 
   Dim childExpressions As New List( Of FilterExpressionBase )()

   Dim country As String
   For Each country In m_frenchCountries 
      Dim expression As New FilterExpression( "ShipCountry", FilterOperator.Equal, country, False )
      childExpressions.Add( expression )
   Next country 

   Return New OrFilterExpression( childExpressions )
End Function 

Private m_filterExpression As OrFilterExpression = Nothing
Private Sub CheckBox_Checked( ByVal sender As Object, ByVal e As RoutedEventArgs )
   If m_filterExpression Is Nothing Then
      m_filterExpression = Me.CreateFilterExpression()
   End If 

   Me.sldgDataGridControl.FilterExpression = m_filterExpression
End Sub 

Private Sub CheckBox_Unchecked( ByVal sender As Object, ByVal e A RoutedEventArgs )
   Me.sldgDataGridControl.FilterExpression = Nothing
End Sub
    private List<string> m_frenchCountries = new List<string>( new string[ 27 ] 
       { "Belgium", "Benin", "Burkina-Faso", "Burundi", 
         "Cameroon", "Canada", "Central African Republic", "Chad", "Comoros", 
         "Congo", "Djibouti", "France", "Gabon", "Guinea", "Haiti", "Ivory Coast", 
         "Luxembourg", "Madagascar", "Mali", "Monaco", "Niger", "Rwanda", 
         "Senegal", "Seychelles", "Switzerland", "Togo", "Vanuatu" } );

private OrFilterExpression CreateFilterExpression()
{
   List<FilterExpressionBase> childExpressions = new List<FilterExpressionBase>();

   foreach( string country in m_frenchCountries )
   {
      FilterExpression expression = new FilterExpression( "ShipCountry", FilterOperator.Equal, country, false );
      childExpressions.Add( expression );
   }

   return new OrFilterExpression( childExpressions );
}

private OrFilterExpression m_filterExpression = null;
private void CheckBox_Checked( object sender, RoutedEventArgs e )
{
   if( m_filterExpression == null )
      m_filterExpression = this.CreateFilterExpression();

   this.sldgDataGridControl.FilterExpression = m_filterExpression;
}

private void CheckBox_Unchecked( object sender, RoutedEventArgs e )
{
   this.sldgDataGridControl.FilterExpression = null;
}
    Inheritance Hierarchy

    System.Object
       Xceed.Wpf.Data.FilterExpressionBase
          Xceed.Wpf.Data.FilterExpressionOperator
             Xceed.Wpf.Data.OrFilterExpression

    Public Constructors
     NameDescription
    Public ConstructorOrFilterExpression ConstructorOverloaded. Initializes a new instance of the OrFilterExpression class.  
    Top
    Public Properties
     NameDescription
    Public PropertyChildExpressionsGets a list of the child filter expressions. (Inherited from Xceed.Wpf.Data.FilterExpressionOperator)
    Top
    Public Methods
     NameDescription
    Public MethodAddAdds a child filter expression, which will be used as part of a logical filter operation. (Inherited from Xceed.Wpf.Data.FilterExpressionOperator)
    Public MethodEqualsOverridden. Determines whether two objects are equal.  
    Public MethodGetHashCodeOverridden. Returns the hash code for this instance.  
    Top
    Supported Frameworks

    .NET: net5.0, net5.0-windows, net6.0, net6.0-macos, net6.0-windows, net7.0, net7.0-macos, net7.0-windows, net8.0, net8.0-browser, net8.0-macos, net8.0-windows, net9.0, net9.0-browser, net9.0-macos, net9.0-windows, net10.0, net10.0-browser, net10.0-macos, net10.0-windows.

    .NET Framework: net40, net403, net45, net451, net452, net46, net461, net462, net463, net47, net471, net472, net48, net481.

    See Also

    Reference

    OrFilterExpression Members
    Xceed.Wpf.Data Namespace
    cf224116-45e2-4539-9fd6-71cc219add2e

    Send Feedback