具有绑定参数问题的WPF ValidationTule

时间:2018-10-18 12:52:48

标签: wpf dependency-properties validationrules

我需要将绑定值传递给验证规则。这是XAML代码:

    <Label Grid.Column="11" Content="Default" Style="{StaticResource labelStyle2}" x:Name="txtTipo" />
<TextBox Grid.Column="12" Style="{StaticResource txtDataStyle1}" Width="100" TextChanged="Data_TextChanged">
    <Binding Path="ConfigObject.Edit.Default" UpdateSourceTrigger="Default">
        <Binding.ValidationRules>
            <local:GenericValidationRule>
                <local:GenericValidationRule.Wrapper>
                    <local:Wrapper TipoInterno="{Binding ElementName=txtTipo, Path=Content}"/>
                </local:GenericValidationRule.Wrapper>
            </local:GenericValidationRule>
        </Binding.ValidationRules>
    </Binding>
</TextBox>

隐藏代码:

    public class GenericValidationRule : ValidationRule
{
    public Wrapper Wrapper { get; set; }

    public override ValidationResult Validate(object value, CultureInfo cultureInfo)
    {
        var xx = Wrapper.TipoInternoProperty;   //TEST
        return new ValidationResult(is_valid, error_context);
    }
}

public class Wrapper : DependencyObject
{
    public static readonly DependencyProperty TipoInternoProperty = DependencyProperty.Register("TipoInterno", typeof(string), typeof(Wrapper), new PropertyMetadata(string.Empty));
    public string TipoInterno
    {
        get { return (string)GetValue(TipoInternoProperty); }
        set { SetValue(TipoInternoProperty, value); }
    }
}

基本上,我无法将所需的值添加到我的TinoInterno属性中。如果我将这样的值硬编码:

<local:Wrapper TipoInterno="TEST" />

该属性已正确评估。在第一种情况下,我需要使用elementName txtTipo传递控件的属性Content。 怎么了?

1 个答案:

答案 0 :(得分:1)

您应该在TipoInterno中获得Wrapper实例的ValidationRule的值:

public override ValidationResult Validate(object value, CultureInfo cultureInfo)
{
    string s = Wrapper.TipoInterno;
    return ...;
}

然后您可以使用x:Reference进行绑定:

<local:Wrapper TipoInterno="{Binding Path=Content, Source={x:Reference txtTipo}}"/>