C# 为什么不是';是否正在执行我的WPF验证规则?
我不想讲更大的故事,但是我有一个表单上的组合框,它没有/没有正常工作。为了尝试通过实验解决问题,我创建了一个测试WPF项目,并将所有相关代码添加到一个简单的WPF窗口中 在我的原始表单上,当组合框上的C# 为什么不是';是否正在执行我的WPF验证规则?,c#,wpf,validation,xaml,C#,Wpf,Validation,Xaml,我不想讲更大的故事,但是我有一个表单上的组合框,它没有/没有正常工作。为了尝试通过实验解决问题,我创建了一个测试WPF项目,并将所有相关代码添加到一个简单的WPF窗口中 在我的原始表单上,当组合框上的SelectedValue更改时,我可以根据需要执行我的ValidationRule。然而,在将代码复制并粘贴到这个新项目中之后,我可以编译并运行程序而不出错,但我无法让验证器执行 可以肯定的是,我在代码中都放了断点。在我的ValidationRule中,我永远不能点击Validate(…)方法,我
SelectedValue
更改时,我可以根据需要执行我的ValidationRule。然而,在将代码复制并粘贴到这个新项目中之后,我可以编译并运行程序而不出错,但我无法让验证器执行
可以肯定的是,我在代码中都放了断点。在我的ValidationRule
中,我永远不能点击Validate(…)
方法,我也不明白为什么这不起作用。特别是因为这是一个直接复制和粘贴,只需要少量的、最小的名称空间更新,以满足明显的引用需求,而且这在我的原始应用程序中确实有效
下面是所有相关的代码。可以随意复制、粘贴和运行
XAML
<Window Height="270"
Title="MainWindow"
Width="532"
x:Class="WPFDataGridApp13.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:my="clr-namespace:WPFDataGridApp13"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Window.Resources>
<Style TargetType="ComboBox">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=(Validation.Errors)[0].ErrorContent}" />
</Trigger>
</Style.Triggers>
</Style>
<ControlTemplate x:Key="validationTemplate">
<Grid>
<Border BorderThickness="1" BorderBrush="Red" >
<AdornedElementPlaceholder />
</Border>
</Grid>
</ControlTemplate>
</Window.Resources>
<StackPanel>
<ComboBox x:Name="myEntityComboBox"
DisplayMemberPath="myEntityName" SelectedValuePath="myEntityId"
Validation.ErrorTemplate="{StaticResource validationTemplate}"
VerticalAlignment="Center" Margin="5">
<ComboBox.SelectedValue>
<Binding Path="myEntityId"
Mode="TwoWay"
NotifyOnValidationError="True"
NotifyOnTargetUpdated="True"
NotifyOnSourceUpdated="True"
ValidatesOnExceptions="True"
ValidatesOnDataErrors="True"
UpdateSourceTrigger="PropertyChanged">
<!--<Binding.ValidationRules>
<my:NonNullValidator/>
</Binding.ValidationRules>-->
</Binding>
</ComboBox.SelectedValue>
</ComboBox>
<Button Content="Select a null value." Click="Button_Click" Margin="5"/>
</StackPanel>
</Window>
窗口代码隐藏
using System;
using System.Collections.ObjectModel;
using System.Linq;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
namespace WPFDataGridApp13
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
myEntityComboBox.SelectedIndex = 0;
myEntityComboBox.ItemsSource = new[]
{
new { myEntityId = (int?)null, myEntityName="Null Option"},
new { myEntityId = (int?)1, myEntityName="#1"},
new { myEntityId = (int?)2, myEntityName="#2"}
};
Binding b = BindingOperations.GetBinding(myEntityComboBox, ComboBox.SelectedValueProperty);
b.ValidationRules.Clear();
b.ValidationRules.Add(new WPFDataGridApp13.NonNullValidator());
}
private void myEntityComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
}
private void Button_Click(object sender, RoutedEventArgs e)
{
myEntityComboBox.SelectedIndex = 0;
}
}
public class NonNullValidator : ValidationRule
{
public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
{
return value == null
? new ValidationResult(false, "Gruu!")
: new ValidationResult(true, null);
}
}
}
使用系统;
使用System.Collections.ObjectModel;
使用System.Linq;
使用系统组件模型;
使用System.Windows;
使用System.Windows.Controls;
使用System.Windows.Data;
命名空间WPFDataGridApp13
{
///
///MainWindow.xaml的交互逻辑
///
公共部分类主窗口:窗口
{
公共主窗口()
{
初始化组件();
myEntityComboBox.SelectedIndex=0;
myEntityComboBox.ItemsSource=new[]
{
新的{myEntityId=(int?)null,myEntityName=“null选项”},
新的{myEntityId=(int?)1,myEntityName=“#1”},
新的{myEntityId=(int?)2,myEntityName=“#2”}
};
Binding b=BindingOperations.GetBinding(myEntityComboBox、ComboBox.SelectedValueProperty);
b、 ValidationRules.Clear();
b、 Add(新的WPFDataGridApp13.NonNullValidator());
}
private void myEntityComboBox_SelectionChanged(对象发送方,SelectionChangedEventArgs e)
{
}
私有无效按钮\u单击(对象发送者,路由目标e)
{
myEntityComboBox.SelectedIndex=0;
}
}
公共类非NullValidator:ValidationRule
{
公共覆盖验证结果验证(对象值,System.Globalization.CultureInfo CultureInfo)
{
返回值==null
?新的ValidationResult(错误,“Gruu!”)
:新的ValidationResult(true,null);
}
}
}
请注意,我的NotNullValidator
的XAML声明是我最初指定验证器的方法,也是我设置此属性的首选方法
我已经注释了它,并在我的代码隐藏文件中设置了验证器,但这也不起作用。无论我尝试什么,我都无法在我的非空验证器
类上点击验证
方法
发生了什么事?您的绑定有一些问题。请参阅下面的代码。您需要将所选组合值绑定到某个属性
<Window x:Class="IconicZip_Learning.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:my="clr-namespace:IconicZip_Learning"
Title="Window1" Height="300" Width="300">
<Window.Resources>
<Style TargetType="ComboBox">
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=(Validation.Errors)[0].ErrorContent}" />
</Trigger>
</Style.Triggers>
</Style>
<ControlTemplate x:Key="validationTemplate">
<Grid>
<Border BorderThickness="1" BorderBrush="Red" >
<AdornedElementPlaceholder />
</Border>
</Grid>
</ControlTemplate>
</Window.Resources>
<StackPanel>
<ComboBox x:Name="myEntityComboBox"
DisplayMemberPath="myEntityName" SelectedValuePath="myEntityId"
Validation.ErrorTemplate="{StaticResource validationTemplate}"
VerticalAlignment="Center" Margin="5">
<ComboBox.SelectedValue>
<Binding Path="SelectedEntity"
RelativeSource="{RelativeSource Mode=FindAncestor,
AncestorType=Window}"
Mode="TwoWay"
NotifyOnValidationError="True"
NotifyOnTargetUpdated="True"
NotifyOnSourceUpdated="True"
ValidatesOnExceptions="True"
ValidatesOnDataErrors="True"
UpdateSourceTrigger="Default"
>
<Binding.ValidationRules>
<my:NonNullValidator ValidatesOnTargetUpdated="True"/>
</Binding.ValidationRules>
</Binding>
</ComboBox.SelectedValue>
</ComboBox>
<Button Content="Select a null value." Click="Button_Click" Margin="5"/>
</StackPanel>
啊哈!非常感谢。成功了。
public partial class Window1 : Window,INotifyPropertyChanged
{
private int? myVar;
public int? SelectedEntity
{
get { return myVar; }
set { myVar = value; OnPropChanged("SelectedEntity"); }
}
public Window1()
{
InitializeComponent();
myEntityComboBox.ItemsSource = new[]
{
new { myEntityId = (int?)null, myEntityName="Null Option"},
new { myEntityId = (int?)1, myEntityName="#1"},
new { myEntityId = (int?)2, myEntityName="#2"}
};
myEntityComboBox.SelectedIndex = 0;
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropChanged(string propName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
private void myEntityComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
}
private void Button_Click(object sender, RoutedEventArgs e)
{
myEntityComboBox.SelectedIndex = 0;
}
}
public class NonNullValidator : ValidationRule
{
public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
{
return value == null
? new ValidationResult(false, "Gruu!")
: new ValidationResult(true, null);
}
}