Question

I have couple of textboxes with custom validators:
(I don t mind if "wrong" data is sent back to object (the property is string), I just need to prevent the functionality of a button if there is an error, so if the binding is not the right place for that kind of validation please tell. I just like the Validation.ErrorTemplate support that i can use)

<ControlTemplate x:Key="validator" >
    <DockPanel LastChildFill="True">
       <TextBlock DockPanel.Dock="Right" Foreground="Red" FontSize="12pt">!</TextBlock>
       <Border BorderBrush="Red" BorderThickness="1.0">
            <AdornedElementPlaceholder />
       </Border>
    </DockPanel>
</ControlTemplate>

<TextBox Height="23" Width="150"  TextWrapping="Wrap"
         Validation.ErrorTemplate="{StaticResource validator}">
         <TextBox.Text>
            <Binding Path="StringProperty" UpdateSourceTrigger="LostFocus">
               <Binding.ValidationRules>
                   <local:NumbersOnly/>
               </Binding.ValidationRules>
            </Binding>
        </TextBox.Text>
</TextBox>

How can I disable specific button if any of the validation error is raised?

<Button Content="DO Work"  Height="57" HorizontalAlignment="Left"  Name="button1" VerticalAlignment="Top" Width="234" Click="button1_Click" />

Answer 1

您可使用<条码>MultiDataTrigger,Style.Triggers>。让我们假设,我们有一个名为“txtName”的“TextBoxTextBox的确认错误作出“btnSave”的区分。

你们可以做些什么:

<Button Content="Save" 
        Grid.Column="1"
        Grid.Row="3"
        HorizontalAlignment="Right"
        Height="23" 
        Name="btnSave" 
        Width="75"
        IsDefault="True"
        Command="{Binding SaveProtocolCommand}"
        Margin="3">
  <Button.Style>
    <Style TargetType="Button">
      <Setter Property="IsEnabled" Value="False"/>
      <Style.Triggers>
        <MultiDataTrigger>
          <MultiDataTrigger.Conditions>
            <Condition Binding="{Binding Path=(Validation.HasError), ElementName=txtName}" Value="False"/>
          </MultiDataTrigger.Conditions>
          <Setter Property="IsEnabled" Value="True"/>
        </MultiDataTrigger>
      </Style.Triggers>
    </Style>
  </Button.Style>
</Button>

希望这将有助于你们。

Answer 2

CanExecute in MVVM is for accreditation management but people use it for accreditation. 最好的办法是在XAML中做到这一点。如果你拥有多个领域来验证,那么你将需要一个转换器(,InverseAndBooleans ToBooleanConver是我对多种诱杀器价值观的实施)。如何这样做:

XAML 代码(如果XAML 代码确实显示,因为即使我尝试过,我还是可以显示):

<Button Name="Button_Test" Content="Test">
    <Button.IsEnabled>
        <MultiBinding Converter="{StaticResource InverseAndBooleansToBooleanConverter}" Mode="TwoWay">
            <Binding ElementName="TextBox_Field1" Path="(Validation.HasError)" />
            <Binding ElementName="TextBox_Field2" Path="(Validation.HasError)" />
            <Binding ElementName="TextBox_Field3" Path="(Validation.HasError)" />
        </MultiBinding>
    </Button.IsEnabled>
</Button>

www.un.org/Depts/DGACM/index_spanish.htm 兑换商

public class InverseAndBooleansToBooleanConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (values.LongLength > 0)
        {
            foreach (var value in values)
            {
                if (value is bool && (bool)value)
                {
                    return false;
                }
             }
        }    
        return true;
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
    {
            throw new NotImplementedException();
    }
}

Answer 3

www.un.org/Depts/DGACM/index_spanish.htm 在您的文本Block中添加:

Validation.Error="Save_Error"

<CodeBehind (xaml.cs):

public partial class MyView : Window
{
    private int _noOfErrorsOnScreen = 0;

    public MyView()
    {
        InitializeComponent();
    }


    private void Save_Error(object sender, ValidationErrorEventArgs e)
    {
        if (e.Action == ValidationErrorEventAction.Added)
            _noOfErrorsOnScreen++;
        else
            _noOfErrorsOnScreen--;

        Save.IsEnabled = _noOfErrorsOnScreen > 0 ? false : true;

    }
}

Answer 4

If you use MVVM then just implement a method CanExecute of interface ICommand. Button doesn t become disabled when command CanExecute is false

如果你在编码背后写上你的逻辑,那么就只能使用一个纽芬兰州的财产:

xaml:

<Button Name=_btn/>

Some:

_btn.IsEnabled=false;

Answer 5

just have a look at this linl

Disable Save button in WPF if validation fails

友情链接