WPF 使用元素 属性 作为索引值绑定到单个列表项

WPF Binding To Single List Item Using Element Property As Index Value

我正在尝试绑定到集合中的单个项目,但我需要能够从元素中传入一个值作为索引。以下是我要完成的示例。

ViewModel

public Dictionary<string, string> ListOfString = new Dictionary<string, string>
{ 
    {"0", "TextToDisplay" }
};

查看

<TextBox Tag="0" Text="{Binding ListOfString[Self.Tag]}" />

我不确定如何获取 TextBox.Tag 的值并将其传递给 ListOfString

您可以使用 MultivalueConverter,您将在其中传递 ListOfStrings DictionaryTextBoxTag 属性,例如所以:

  <Window.Resources>
    <ns:ValuFromDicConverter x:Key="ValuFromDicConverter"/>
</Window.Resources>
<Grid>
    <TextBox Tag="0" x:Name="tb">
        <TextBox.Text>
            <MultiBinding Converter="{StaticResource ValuFromDicConverter}">
                <Binding Path="ListOfString"/>
                <Binding ElementName="tb" Path="Tag"></Binding>
            </MultiBinding>
        </TextBox.Text>
    </TextBox>
</Grid>

转换器将简单地获取 Dictionary:

中的相应值
 public class ValuFromDicConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
    {
        if (values == null) return null;
        return (values[0] as Dictionary<string, string>)[values[1].ToString()];

    }

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

并且不要忘记将字典定义为 属性 并设置 DataContext

    private Dictionary<string, string> _listOfString = new Dictionary<string, string>
    { 
        {"0", "TextToDisplay" }
    };


    public Dictionary<string, string> ListOfString
    {
        get
        {
            return _listOfString;
        }

        set
        {
            if (_listOfString.Equals(value))
            {
                return;
            }

            _listOfString = value;

        }
    }