C# WPF ComboBox ItemsSource 绑定问题

Question

我在将 ComboBox ItemsSource 与列表绑定时遇到问题。 我从 csv 文件中读取了工作场所。 它看不到工作场所列表。 请告诉我哪里出了问题。 xaml：

    <ComboBox Grid.Column="1" Grid.Row="9" Height="25" Margin="0,18,0,0" ItemsSource="{Binding Workplaces}">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <TextBlock Text="{Binding title}" />
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>

xaml.cs：

public partial class MainWindow : Window
{
   private BindableCollection<WorkplaceInfo> Workplaces { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        Workplaces = new BindableCollection<WorkplaceInfo>(GetWorkplaces());
    }

    private List<WorkplaceInfo> GetWorkplaces()
    {
        List<WorkplaceInfo> workplaces = new List<WorkplaceInfo>();

        using (var streamReader = new StreamReader("Workplaces.csv"))
        {
            using (var csvReader = new CsvReader(streamReader, CultureInfo.InvariantCulture))
            {
                //csvReader.Context.RegisterClassMap<WorkplaceInfoClassMap>();
                var workplaceInfoList = csvReader.GetRecords<dynamic>().ToList();
                foreach (var wi in workplaceInfoList)
                {
                    workplaces.Add(new WorkplaceInfo(wi.title, wi.member_of.Split(";")));  
                }
            }
        }
        return workplaces;
    }
}

工作场所信息 class：

class WorkplaceInfo
{
    public String title { get; }
    public String[] memberOfList { get; }

    public WorkplaceInfo(string title, string[] memberOfList)
    {
        this.title = title;
        this.memberOfList = memberOfList;
    } 
}

Answer 1

这是您优化后的代码：

   public ObservableCollection<WorkplaceInfo> Workplaces { get; set; }

    public MainWindow()
    {
        this.DataContext = this;
        Workplaces = new ObservableCollection<WorkplaceInfo>(GetWorkplaces());
        InitializeComponent();


    }

    private List<WorkplaceInfo> GetWorkplaces()
    {
        List<WorkplaceInfo> workplaces = new List<WorkplaceInfo>();

        try
        {
            using (var streamReader = new StreamReader("Workplaces.csv"))
            {
                using (var csvReader = new CsvReader(streamReader, CultureInfo.CurrentCulture))
                {
                    //csvReader.Context.RegisterClassMap<WorkplaceInfoClassMap>();
                    var workplaceInfoList = csvReader.GetRecords<dynamic>().ToList();
                    foreach (var wi in workplaceInfoList)
                    {
                        var titl = wi.title;

                        workplaces.Add(new WorkplaceInfo(wi.title, new List<string>() { wi.member_of }.ToArray()));
                    }
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
        return workplaces;
    }

因此，您的代码中需要进行的更改是：

1. 将您的 Workplaces 集合设置为公共 ObservableCollection
2. 添加 DataContext 绑定
3. 读入日期并在主 window 初始化之前创建集合（否则 UI 不会检测到你 object 的变化，除非你实现 INotifyPropertyChanged 事件）

ps 我不知道你的 csv 文件的结构所以我制作了我的小演示（Workplaces.csv）并采用了解析器。 如果它与您的 csv 文件结构匹配，您可以保留解析器。：

title;member_of 
London;First 
Amsterdam;Second

我的热情建议是在处理文件和处理应用程序外部的任何内容时始终使用 try-catch 块。

最好的祝福。