WPF將selectedItem值綁定

詞典：

public Dictionary<string,DateTime> TimeItems { get; set; }

<ComboBox Grid.Column="3" 
     HorizontalContentAlignment="Center" 
     VerticalContentAlignment="Center" 
     ItemsSource="{Binding TimeItems}" 
     SelectedIndex="0" 
     SelectedItem="{Binding SelectedItem}">

我怎麼能結合的TimeItems

來源

2015-09-21 A191919

Dictionary的元素是KeyValuePair ，所以你可以通過該結構的屬性Value來獲得DateTime部分。無論如何，使用Dictionary作爲數據源並不是個好主意。 – Spawn

-1

public DateTime SelectedItem { get; set; }值試試這個：

foreach (KeyValuePair<string,DateTime> values in TimeItems){ 
     comboBox.Items.Add(values.Value); 
     }

來源

2015-09-21 07:44:08

它做什麼？它是如何工作的？請添加解釋，以使這個答案對未來的訪問者更有用。謝謝！ – Vogel612

您可以使用轉換器將Dictionary的值綁定到SelectedItem。

public class DictionaryValueConverter : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     return value; 
    } 

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     return ((KeyValuePair<string, DateTime>)value).Value; 
    } 
}

XAML

<ComboBox Grid.Column="3" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" 
    ItemsSource="{Binding TimeItems}" 
    SelectedItem="{Binding SelectedItem, Converter={StaticResource DictionaryValueConverter}}" />

來源

2015-09-21 07:47:24 daniel

如果你只在顯示和檢索Dcitionary的值，則可以使用下面的選項

視圖模型

class ExpenseViewModel : INotifyPropertyChanged 
{ 
    public event PropertyChangedEventHandler PropertyChanged; 
    public void NotifyPropertyChanged(string propName) 
    { 
     var pc = PropertyChanged; 
     if (pc != null) 
     { 
      pc(this, new PropertyChangedEventArgs(propName)); 
     } 
    } 

    private void Populate() 
    { 
     _mySource.Add("Test 1", DateTime.Now); 
     _mySource.Add("Test 2", DateTime.Now.AddDays(1)); 
     _mySource.Add("Test 3", DateTime.Now.AddDays(2)); 
     _mySource.Add("Test 4", DateTime.Now.AddDays(3)); 
     NotifyPropertyChanged("MySource"); 
    } 
    private Dictionary<string, DateTime> _mySource; 
    public Dictionary<string, DateTime> MySource 
    { 
     get { return _mySource; } 
    } 

    public ExpenseViewModel() 
    { 
     _mySource = new Dictionary<string, DateTime>(); 
     Populate(); 
    } 
    public DateTime SelectedDate 
    { 
     get; 
     set; 
    } 
}

感興趣View.xaml

<StackPanel HorizontalAlignment="Left"> 
    <StackPanel.Resources> 
     <local:Converters x:Key="Converter"/> 
    </StackPanel.Resources> 
    <ComboBox x:Name="cmbBox" Width="200" Margin="10,0,20,0" ItemsSource="{Binding MySource, Converter={StaticResource Converter}}" 
      SelectedItem="{Binding SelectedDate, Mode=TwoWay}" Height="20"> 

    </ComboBox> 
</StackPanel>

，當地是該項目的含轉換器轉換

public class Converters : IValueConverter 
{ 
    private static readonly PropertyInfo InheritanceContextProp = typeof(DependencyObject).GetProperty("InheritanceContext", BindingFlags.NonPublic | BindingFlags.Instance); 

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) 
    { 
     var dic = value as Dictionary<string, DateTime>; 
     return dic.Values; 
    } 

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     throw new NotImplementedException(); 
    } 
}

鑑於後面的代碼我剛纔定義在DataContext

來源

2015-09-21 08:02:27 Sandesh

您可以設置SelectedValuePath爲「價值」的XMLNS（因爲每個項目都是KeyValuePair），然後將SelectedValue屬性綁定到您的屬性：

<ComboBox Grid.Column="3" 
    HorizontalContentAlignment="Center" 
    VerticalContentAlignment="Center" 
    ItemsSource="{Binding TimeItems}" 
    SelectedIndex="0" 
    SelectedValuePath="Value" 
    SelectedValue="{Binding SelectedItem}"/>

來源

2015-09-21 08:55:12 user1064519

WPF將selectedItem值綁定

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