Databindings are not working

Question

I have made a small Project where I have a wcf service and an wpf app to look up weather data in between certain dates. At first, everything was fine, but when I used Databindings, the Datagrid stayed emty. Can someone help me?

//WCF interface:
public interface IService1
    {
        [OperationContract]
        List<WeatherDataContract> GetWeatherData(DateTime start, DateTime end);
    }

    [DataContract]
    public class WeatherDataContract
    {
        [DataMember]
        public int Id { get; set; }
        [DataMember]
        public DateTime Datum { get; set; }
        [DataMember]
        public TimeSpan Zeit { get; set; }
        [DataMember]
        public double Temperatur { get; set; }
        [DataMember]
        public int Luftdruck { get; set; }
        [DataMember]
        public int Regen { get; set; }
        [DataMember]
        public double Wind { get; set; }
        [DataMember]
        public int Richtung { get; set; }
        [DataMember]
        public int Feuchtigkeit { get; set; }
    }
//WCF service
WeatherDataEntities weatherDataEntities = new WeatherDataEntities();
        public List<WeatherDataContract> GetWeatherData(DateTime start, DateTime end)
        {

            return (from weather in weatherDataEntities.WeatherDatas
                    where weather.Datum <= end && weather.Datum >= start
                    select new WeatherDataContract
                    {
                        Id = weather.Id,
                        Datum = (DateTime)weather.Datum,
                        Zeit = (TimeSpan)weather.Zeit,
                        Temperatur = (double)weather.Temperatur,
                        Luftdruck = (int)weather.Luftdruck,
                        Regen = (int)weather.Regen,
                        Wind = (int)weather.Wind,
                        Richtung = (int)weather.Richtung,
                        Feuchtigkeit = (int)weather.Feuchtigkeit
                    }).Take(100).ToList();
        }
//XAML:
<DataGrid x:Name="weatherDataGrid" HorizontalAlignment="Left" Height="355" Margin="21,35,0,0" VerticalAlignment="Top" Width="742" AutoGenerateColumns="False">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding Id}"/>
            <DataGridTextColumn Binding="{Binding Datum}"/>
            <DataGridTextColumn Binding="{Binding Zeit}"/>
            <DataGridTextColumn Binding="{Binding Temperatur}"/>
            <DataGridTextColumn Binding="{Binding Luftdruck}"/>
            <DataGridTextColumn Binding="{Binding Regen}"/>
            <DataGridTextColumn Binding="{Binding Wind}"/>
            <DataGridTextColumn Binding="{Binding Richtung}"/>
            <DataGridTextColumn Binding="{Binding Feuchtigkeit}"/>
        </DataGrid.Columns>
    </DataGrid>
    <DatePicker SelectedDateChanged="Date_SelectedDateChanged" x:Name="fromDate" HorizontalAlignment="Left" Margin="75,10,0,0" VerticalAlignment="Top" Width="150"/>
    <DatePicker SelectedDateChanged="Date_SelectedDateChanged" x:Name="toDate" HorizontalAlignment="Left" Margin="287,9,0,0" VerticalAlignment="Top" Width="136"/>
    <Label Content="From" HorizontalAlignment="Left" Margin="33,8,0,0" VerticalAlignment="Top"/>
    <Label Content="To" HorizontalAlignment="Left" Margin="260,10,0,0" VerticalAlignment="Top"/>

//xaml.cs
ServiceReference1.Service1Client client = new ServiceReference1.Service1Client();

        public List<ServiceReference1.WeatherDataContract> WeatherData
        {
            get
            {
                return client.GetWeatherData(fromDate.SelectedDate ?? DateTime.MinValue, toDate.SelectedDate ?? DateTime.MaxValue).ToList();
            }
        }

        public MainWindow()
        {
            InitializeComponent();
        }

        private void Date_SelectedDateChanged(object sender, SelectionChangedEventArgs e)
        {
            weatherDataGrid.ItemsSource = WeatherData;
        }
    }

Answer 1

For data binding you should implement INotifyPropertyChanged
https://learn.microsoft.com/en-us/dotnet/api/system.componentmodel.inotifypropertychanged?view=net-6.0
https://learn.microsoft.com/en-us/dotnet/desktop/winforms/how-to-implement-the-inotifypropertychanged-interface?view=netframeworkdesktop-4.8

Answer 2

namespace LinqExample
{
public partial class MainWindow : Window
{

    public MainWindow()
    {
        InitializeComponent();
        LoadData();
    }

    public void LoadData()
    {
        XElement xElement = XElement.Load(@"..\..\cd_catalog.xml");
        XNamespace ns = "http://tempuri.org/CDCatalog.xsd";

        var query = from email in xElement.Descendants(ns + "CD")
                    where email.Element(ns + "TITLE").Value.Contains(fromPersonTextBox.Text)
                    select new CDCatalog()
                    {
                        Title = email.Element(ns + "TITLE").Value,
                        Artist = email.Element(ns + "ARTIST").Value,
                        Country = email.Element(ns + "COUNTRY").Value,
                        Company = email.Element(ns + "COMPANY").Value,
                        Price = email.Element(ns + "PRICE").Value,
                        Year = email.Element(ns + "YEAR").Value
                    };

        emailDataGrid.ItemsSource = query;
    }

    private void OnTextChanged(object sender, TextChangedEventArgs e)
    {
        LoadData();
    }
}

}

Answer 3

ServiceReference1.Service1Client client = new ServiceReference1.Service1Client();
public MainWindow()
{
InitializeComponent();
}

    private void Bbutton_Click(object sender, RoutedEventArgs e)
    {
        DdataGrid.ItemsSource = client.GetPerson(TtextBox.Text);
    }

Answer 4

CD

public partial class frmCDVerwaltung : Form
{
public frmCDVerwaltung()
{
InitializeComponent();
sqlDataAdapter1.Fill(dataSet11, "CD");
}

    private void btnRecreate_Click(object sender, EventArgs e)  
    {  
        if (openFileDialog1.ShowDialog() == DialogResult.OK)  
        {  
            dataSet11.Clear();  
            dataSet11.ReadXml(openFileDialog1.FileName);  
            clearDatabase();  
            updateDatabase();  
        }  
    }  

    private void btnUpdate_Click(object sender, EventArgs e)  
    {  
        dataSet11.Clear();  
        sqlDataAdapter1.Fill(dataSet11, "CD");  
    }  

    private void btnDelete_Click(object sender, EventArgs e)  
    {  
        if (dataGridView1.SelectedRows != null)  
        {  
            foreach (DataGridViewRow dr in dataGridView1.SelectedRows)  
            {  
                dataGridView1.Rows.Remove(dr);  
            }  
            updateDatabase();  
        }  
    }  

    private void clearDatabase()  
    {  
        SqlCommand cmd = new SqlCommand("delete from CD where 1 = 1", sqlConnection1);  
        sqlConnection1.Open();  

        cmd.ExecuteNonQuery();  

        sqlConnection1.Close();  
    }  

    private void dgvCD_CellEndEdit(object sender, DataGridViewCellEventArgs e)  
    {  
        updateDatabase();          
    }  

    private void updateDatabase()  
	{  
        sqlDataAdapter1.Update(dataSet11, "CD");  
    }  

	private void dgvCD_CellEnter(object sender, DataGridViewCellEventArgs e)  
	{  
        updateDatabase();  
    }  
}  

Answer 5

https://learn.microsoft.com/en-us/visualstudio/data-tools/walkthrough-creating-a-simple-wcf-service-in-windows-forms?view=vs-2022&tabs=csharp