Question

我希望使用工具提示进行库存/标准红色边框验证，以显示我的UserControl。见下面的代码。我有主页和UserControl。

UserControl有文本框和按钮。 UserControls绑定到Id属性并在TextBox中显示此Id。

主页面包含UserControl和TextBox。它们绑定到FirstValue和SecondValue。这两个属性都会引发错当我在文本框中输入/更改内容时 - 我看到边框和摘要。当我在UserControl中更改文本时 - 我在摘要中看到错误但没有边框，当我点击错误时 - 它聚焦按钮，不会转到TextBox。我该如何解决这个问题？我希望整个UserControl在红色边框内。

MainPage XAML：

<UserControl x:Class="SilverlightApplication1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="275" d:DesignWidth="402" xmlns:my="clr-namespace:SilverlightApplication1" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">

    <Grid x:Name="LayoutRoot" Background="White" Width="300" HorizontalAlignment="Left">
        <Grid.RowDefinitions>
            <RowDefinition Height="30" />
            <RowDefinition Height="40" />
            <RowDefinition Height="30" />
            <RowDefinition Height="30" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <TextBox Grid.Row="2" Margin="3" Text="{Binding SecondValue, Mode=TwoWay, NotifyOnValidationError=True}"/>
        <my:TestUserControl Margin="3" Id="{Binding FirstValue, Mode=TwoWay, NotifyOnValidationError=True}"/>
        <sdk:ValidationSummary Grid.Row="4" Name="validationSummary1" />
    </Grid>
</UserControl>

MainPage CS

using System.Windows.Controls;


namespace SilverlightApplication1
{
    using System;
    using System.Collections;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Linq;

    public partial class MainPage : UserControl, INotifyDataErrorInfo, INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;
        public event EventHandler<DataErrorsChangedEventArgs> ErrorsChanged;
        readonly Dictionary<string, List<string>> _currentErrors;

        private string _firstValue;
        private string _secondValue;

        public MainPage()
        {
            InitializeComponent();
            _currentErrors = new Dictionary<string, List<string>>();
            _firstValue = "test1";
            _secondValue = "test2";
            LayoutRoot.DataContext = this;
        }


        public string FirstValue
        {
            get { return _firstValue; }

            set
            {
                _firstValue = value;
                CheckIfValueIsValid("FirstValue", value);
                this.OnPropertyChanged("FirstValue");
            }
        }

        public string SecondValue
        {
            get { return _secondValue; }
            set
            {
                _secondValue = value;
                CheckIfValueIsValid("SecondValue", value);
                this.OnPropertyChanged("SecondValue");
            }
        }

        public void CheckIfValueIsValid(string propertyName, string value)
        {
            ClearErrorFromProperty(propertyName);

            AddErrorForProperty(propertyName, "Bad value");
        }

        protected void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

        public IEnumerable GetErrors(string propertyName)
        {
            if (string.IsNullOrEmpty(propertyName))
            {
                return (_currentErrors.Values);
            }
            MakeOrCreatePropertyErrorList(propertyName);

            return _currentErrors[propertyName];
        }

        public bool HasErrors
        {
            get
            {
                return (_currentErrors.Where(c => c.Value.Count > 0).Count() > 0);
            }
        }

        void FireErrorsChanged(string property)
        {
            if (ErrorsChanged != null)
            {
                ErrorsChanged(this, new DataErrorsChangedEventArgs(property));
            }
        }

        public void ClearErrorFromProperty(string property)
        {
            MakeOrCreatePropertyErrorList(property);

            _currentErrors[property].Clear();
            FireErrorsChanged(property);
        }

        public void AddErrorForProperty(string property, string error)
        {
            MakeOrCreatePropertyErrorList(property);
            _currentErrors[property].Add(error);
            FireErrorsChanged(property);
        }

        void MakeOrCreatePropertyErrorList(string propertyName)
        {
            if (!_currentErrors.ContainsKey(propertyName))
            {
                _currentErrors[propertyName] = new List<string>();
            }
        }


    }
}

UserControl XAML：

<UserControl x:Class="SilverlightApplication1.TestUserControl"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="30" d:DesignWidth="400">

    <Grid x:Name="LayoutRoot" Background="White">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*" />
            <ColumnDefinition Width="Auto" />
        </Grid.ColumnDefinitions>
        <Button Content="..." Grid.Column="1" Padding="10,0" />
        <TextBox Text="{Binding Id, Mode=TwoWay}" />
    </Grid>
</UserControl>

UserControl CS：

using System.Windows.Controls;

namespace SilverlightApplication1
{
    using System.ComponentModel;
    using System.Windows;

    public partial class TestUserControl : UserControl, INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        public TestUserControl()
        {
            InitializeComponent();
            LayoutRoot.DataContext = this;
        }


        public string Id
        {
            get { return (string)base.GetValue(IdProperty); }
            set
            {
                base.SetValue(IdProperty, value);
                this.OnPropertyChanged("Id");
            }
        }

        public static DependencyProperty IdProperty =
            DependencyProperty.Register(
            "Id",
            typeof(string),
            typeof(TestUserControl),
            new PropertyMetadata(OnIdChanged));

        private static void OnIdChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (DesignerProperties.IsInDesignTool) return;

            var lookup = d as TestUserControl;
            lookup.OnPropertyChanged("Id");
        }

        protected void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

    }
}

Answer 1

要使您的示例正常工作，您应该从TestUserControl.xaml.cs文件中删除所有代码并修复绑定。像这样：

<Button Content="..." Grid.Column="1" Padding="10,0" />
<TextBox Text="{Binding FirstValue, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnNotifyDataErrors=True}" />

后面有空代码：

public partial class TestUserControl : UserControl
{
    public TestUserControl()
    {
        InitializeComponent();
    }
}

接下来，你的另一个问题

在所有3个框（一个矩形）周围显示红色边框

可以通过绑定到HasError属性来实现。根据你的代码，它看起来如此：

<Grid x:Name="LayoutRoot" Background="White">
   <!-- ... -->
   <Border BorderBrush="Red" BorderThickness="1" 
            Grid.ColumnSpan="2" IsHitTestVisible="False"
            Visibility="{Binding HasErrors, Converter={StaticResource BooleanToVisibilityConverter}}" />

我添加了红色Border元素，当HasError属性设置为true时，该元素变为可见。但是你应该在代码中的某处调用OnPropertyChanged("HasError")。

另一种方法：创建自定义控件而不是UserControl。我发布了过多描述如何在自定义控件中实现验证作为this question about validation的答案。

我可以做出更具体的答案，但你应该通过将视图模型与视图分开来修复帖子中的代码，因为现在很难根据当前代码实现某些东西。使用INotifyDataErrorInfo检查我关于验证实现的帖子：WPF and Silverlight Validation。

或者您可以下载我的验证课程directly。

之后代码将变得更加简单，我将能够帮助您解决更复杂的问题。

Answer 2

更改

<TextBox Text="{Binding Id, Mode=TwoWay}" />

到

<TextBox Text="{Binding Id, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnDataErrors=True}" />

如何强制验证在UserControl上显示

2 个答案: