c# wpf中组合框的过滤答案

【问题标题】：Filtering of combobox in c# wpfc# wpf中组合框的过滤
【发布时间】：2020-04-01 17:09:04
【问题描述】：

XAML：

<ComboBox x:Name="cmb" HorizontalAlignment="Left" 
              Margin="183,39,0,0" 
              VerticalAlignment="Top" 
              Width="120" 
              ItemsSource="{Binding FilteredNames, Mode=OneWay}"
              IsTextSearchEnabled="True"
              IsEditable="True"
              TextSearch.Text="{Binding Filter, UpdateSourceTrigger=PropertyChanged}"/>

视图模型：

public List<string> FilteredNames
{
    get
    {
        return (names.FindAll(x => x.Contains(filter))).ToList<string>();
    }
}

public string Filter
{
    get
    {
        return this.filter;
    }
    set
    {
        this.filter = value;
        NotifyPropertyChanged("FilteredNames");
    }
}

public ViewModel()
{
    this.names = new List<string>() { "Jerry", "Joey", "Roger", "Raymond", "Jessica", "Mario", 
                                              "Jonathan" };
    this.filter = "";
}

这是我已经实现的。请帮我解决如何在组合框中过滤下拉列表。就像我输入“j”时，我想得到所有包含“j”的项目。

【问题讨论】：

标签： c# wpf combobox filtering

【解决方案1】：

您应该将字符串输入绑定到 ComboBox 的 Text 属性：

Text="{Binding Filter, UpdateSourceTrigger=PropertyChanged}"

我还建议使用CollectionView 进行这样的过滤：

public ICollectionView FilteredNames { get; set; }
IList<string> names = new List<string>() { "Jerry", "Joey", "Roger", "Raymond", "Jessica", "Mario", "Jonathan" };

public VM()
{
    FilteredNames = CollectionViewSource.GetDefaultView(names);
    FilteredNames.Filter = (obj) => 
    {
        if (!(obj is string str))
            return false;

        return str.Contains(filter);
    };
}

string filter = "";
public string Filter
{
    get 
    {
        return this.filter;
    }
    set 
    {
        this.filter = value;
        FilteredNames?.Refresh();
    }
}

【讨论】：