FrameworkElement.BindingGroup Свойство

public:
 property System::Windows::Data::BindingGroup ^ BindingGroup { System::Windows::Data::BindingGroup ^ get(); void set(System::Windows::Data::BindingGroup ^ value); };

[System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)]
public System.Windows.Data.BindingGroup BindingGroup { get; set; }

[<System.Windows.Localizability(System.Windows.LocalizationCategory.NeverLocalize)>]
member this.BindingGroup : System.Windows.Data.BindingGroup with get, set

Public Property BindingGroup As BindingGroup

Значение свойства

BindingGroup

Группа BindingGroup, используемая для элемента.The BindingGroup that is used for the element.

Атрибуты

LocalizabilityAttribute

Примеры

Следующие примеры являются частью приложения, которое проверяет, установил ли пользователь свойства двух объектов равными значениями.The following examples are part of an application that checks whether the user has set the properties of two objects to equal values. В первом примере создаются два TextBox элемента управления, каждый из которых привязан к другому источнику данных.The first example creates two TextBox controls, each of which is bound to a different data source. Содержит StackPanel объект BindingGroup , содержащий объект ValidationRule , который проверяет, равны ли две строки.The StackPanel has a BindingGroup that contains a ValidationRule that checks that the two strings are equal.

<StackPanel>
  <StackPanel.Resources>
    <src:Type1 x:Key="object1" />
    <src:Type2 x:Key="object2" />
  </StackPanel.Resources>

  <StackPanel Name="sp1"
              Margin="5"
              DataContext="{Binding Source={StaticResource object1}}"
              Validation.ValidationAdornerSite="{Binding ElementName=label1}"
              Orientation="Horizontal"
              HorizontalAlignment="Center">

    <StackPanel.BindingGroup>
      <BindingGroup Name="bindingGroup">
        <BindingGroup.ValidationRules>
          <src:BindingGroupValidationRule ValidatesOnTargetUpdated="True" />
        </BindingGroup.ValidationRules>
      </BindingGroup>
    </StackPanel.BindingGroup>

    <TextBlock Text="First string" />

    <TextBox Width="150"
             Text="{Binding Path=PropertyA}" />

    <TextBlock Text="Second string" />

    <TextBox Width="150"
             Text="{Binding Source={StaticResource object2}, 
      Path=PropertyB, BindingGroupName=bindingGroup, 
      TargetNullValue=please enter a string}" />

  </StackPanel>

  <Label Name="label1"
         Content="{Binding ElementName=sp1, Path=(Validation.Errors)[0].ErrorContent}"
         Margin="5"
         Foreground="Red"
         HorizontalAlignment="Center" />

  <Button HorizontalAlignment="Center"
          Click="Button_Click"
          IsDefault="True">
    _Submit
  </Button>

  <StackPanel Orientation="Horizontal">
    <TextBlock Text="First string:"
               FontWeight="Bold" />
    <TextBlock Text="{Binding Source={StaticResource object1}, 
      Path=PropertyA, TargetNullValue=--}" />
  </StackPanel>

  <StackPanel Orientation="Horizontal">
    <TextBlock Text="Second string:"
               FontWeight="Bold" />
    <TextBlock Text="{Binding Source={StaticResource object2}, 
      Path=PropertyB, TargetNullValue=--}" />
  </StackPanel>
</StackPanel>

В следующем примере показано ValidationRule , что в предыдущем примере используется.The following example shows the ValidationRule that the previous example uses. В Validate переопределении метода этот пример получает каждый исходный объект из BindingGroup и проверяет, равны ли свойства объектов.In the Validate method override, the example gets each source object from the BindingGroup and checks whether the properties of the objects are equal.

public class Type1
{
    public string PropertyA { get; set; }

    public Type1()
    {
        PropertyA = "Default Value";
    }
}

public class Type2
{
    public string PropertyB { get; set; }

    public Type2()
    {
    }
}

public class BindingGroupValidationRule : ValidationRule
{
    public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
    {
        BindingGroup bg = value as BindingGroup;

        Type1 object1 = null;
        Type2 object2 = null;

        foreach (object item in bg.Items)
        {
            if (item is Type1)
            {
                object1 = item as Type1;
            }

            if (item is Type2)
            {
                object2 = item as Type2;
            }
        }

        if (object1 == null || object2 == null)
        {
            return new ValidationResult(false, "BindingGroup did not find source object.");
        }

        string string1 = bg.GetValue(object1, "PropertyA") as string;
        string string2 = bg.GetValue(object2, "PropertyB") as string;

        if (string1 != string2)
        {
            return new ValidationResult(false, "The two strings must be identical.");
        }

        return ValidationResult.ValidResult;
    }
}

Public Class Type1
    Public Property PropertyA() As String

    Public Sub New()
        PropertyA = "Default Value"
    End Sub
End Class

Public Class Type2
    Public Property PropertyB() As String

    Public Sub New()
    End Sub
End Class

Public Class BindingGroupValidationRule
    Inherits ValidationRule
    Public Overrides Function Validate(ByVal value As Object, ByVal cultureInfo As System.Globalization.CultureInfo) As ValidationResult
        Dim bg As BindingGroup = TryCast(value, BindingGroup)

        Dim object1 As Type1 = Nothing
        Dim object2 As Type2 = Nothing

        For Each item As Object In bg.Items
            If TypeOf item Is Type1 Then
                object1 = TryCast(item, Type1)
            End If

            If TypeOf item Is Type2 Then
                object2 = TryCast(item, Type2)
            End If
        Next item

        If object1 Is Nothing OrElse object2 Is Nothing Then
            Return New ValidationResult(False, "BindingGroup did not find source object.")
        End If

        Dim string1 As String = TryCast(bg.GetValue(object1, "PropertyA"), String)
        Dim string2 As String = TryCast(bg.GetValue(object2, "PropertyB"), String)

        If string1 <> string2 Then
            Return New ValidationResult(False, "The two strings must be identical.")
        End If

        Return ValidationResult.ValidResult

    End Function

End Class

Для вызова ValidationRule метода вызовите UpdateSources метод.To invoke the ValidationRule, call the UpdateSources method. В следующем примере вызывается UpdateSources , когда возникает событие нажатия кнопки.The following example calls UpdateSources when the click event of the button occurs.

private void Button_Click(object sender, RoutedEventArgs e)
{
    sp1.BindingGroup.UpdateSources();
}

Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    sp1.BindingGroup.UpdateSources()
End Sub

Комментарии

BindingGroupМожно использовать для проверки значений нескольких свойств объекта.A BindingGroup can be used to validate the values of multiple properties of an object. Например, предположим, что приложение предлагает пользователю ввести адрес и затем заполняет объект типа Address , который имеет свойства,, Street City ZipCode и Country , со значениями, предоставленными пользователем.For example, suppose that an application prompts the user to enter an address and then populates an object of type Address, which has the properties Street, City, ZipCode, and Country, with the values that the user provided. Приложение содержит панель, содержащую четыре TextBox элемента управления, каждый из которых привязан к одному из свойств объекта.The application has a panel that contains four TextBox controls, each of which is bound to one of the object's properties. ValidationRuleДля проверки объекта можно использовать в BindingGroup Address .You can use a ValidationRule in a BindingGroup to validate the Address object. Например, ValidationRule может гарантировать, что почтовый индекс действителен для страны или региона адреса.For example, the ValidationRule can ensure that the zip code is valid for the country/region of the address.

Дочерние элементы наследуют BindingGroup от своих родительских элементов, как и любые другие наследуемые свойства.Child elements inherit the BindingGroup from their parent elements, just as with any other inheritable property.

Сведения о свойстве зависимостейDependency Property Information

Поле идентификатораIdentifier field	BindingGroupProperty
Свойства метаданных, для которых задано значение trueMetadata properties set to true	Inherits

Применяется к