MetroWindow 中的数据验证问题

Question

我是 Wpf 的新手，我正在尝试各种控件。我从 Metro Mahapps Demo 中获取了这个 ViewModel，只留下（假设我没有遗漏任何东西）处理数据验证的代码（数量大于 10）：

 public class Modelis : INotifyPropertyChanged, IDataErrorInfo
{
    int? _integerGreater10Property;

    public Modelis(IDialogCoordinator dialogCoordinator)
    {    
    }
    public int? IntegerGreater10Property
    {
        get { return this._integerGreater10Property; }
        set
        {
            if (Equals(value, _integerGreater10Property))
            {
                return;
            }

            _integerGreater10Property = value;
            RaisePropertyChanged("IntegerGreater10Property");
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;

    /// <summary>
    /// Raises the PropertyChanged event if needed.
    /// </summary>
    /// <param name="propertyName">The name of the property that changed.</param>
    protected virtual void RaisePropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    public string this[string columnName]
    {
        get
        {
            if (columnName == "IntegerGreater10Property" && this.IntegerGreater10Property < 10)
            {
                return "Number is not greater than 10";
            }
            return null;
        }
    }

    public string Error { get { return string.Empty; } }
}

然后，我在 Window 中引用了它（也取自演示）：

         xmlns:Registracija="clr-namespace:Registracijos_sistema"
         mc:Ignorable="d"
         d:DesignHeight="600"
         d:DesignWidth="800"
         d:DataContext="{d:DesignInstance Registracija:Modelis}"

但是当我添加一个文本框（再次来自演示）来通知数字是否不大于 10 时，它似乎不起作用：

        <TextBox   
        Controls:TextBoxHelper.Watermark="Number smaller than 10"
        Text="{Binding IntegerGreater10Property, 
        ValidatesOnDataErrors=True, 
        UpdateSourceTrigger=PropertyChanged, 
        NotifyOnValidationError=True}"  
        Margin="104,197,47,104" />

我做错了什么？

Answer 1

尝试将以下内容添加到您的 MetroWindow xaml：

    xmlns:Dialog="clr-namespace:MahApps.Metro.Controls.Dialogs;assembly=MahApps.Metro"
    Dialog:DialogParticipation.Register="{Binding}"

你的 window 代码背后是否有依赖项属性，就像这样？

    public Modelis MyModelis
    {
        get { return (Modelis)GetValue(MyModelisProperty); }
        set { SetValue(MyModelisProperty, value); }
    }

    // Using a DependencyProperty as the backing store for MyModelis.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty MyModelisProperty =
        DependencyProperty.Register("MyModelis", typeof(Modelis), typeof(Window1), new PropertyMetadata(new Modelis(DialogCoordinator.Instance)));

提示：如果您使用的是 Visual Studio，您可以键入 propdp 并点击 'TAB' 让它自动添加代码。之后，只需输入缺失值即可。

然后回到我们的 MetroWindow xaml，更改为：

d:DataContext="{d:DesignInstance Registracija:Modelis}"

对此：

 DataContext="{Binding MyModelis, RelativeSource={RelativeSource Self}}"

MetroWindow 中的数据验证问题

Data validation issue in MetroWindow

c#

wpf

viewmodel