WPF: How to bind object to ComboBox

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Solution 1

There are several ways to tell the framework what to display

1) Use DisplayMemberPath on the ComboBox (this will display the named property):

<ComboBox ItemsSource="{Binding Path=Clients}" 
          DisplayMemberPath="Name"
/>

2) Set ItemTemplate on the ComboBox. This is like #1, except allows you to define a template to display, rather than just a property:

<ComboBox ItemsSource="{Binding Path=Clients}">
    <ComboBox.ItemTemplate>
        <DataTemplate>
            <Border BorderBrush="Green" BorderThickness="1" Padding="5">
                <TextBlock Text="{Binding Path=Name,StringFormat='Name: {0}'}" />
            </Border>
        </DataTemplate>
    </ComboBox.ItemTemplate>
</ComboBox>

3) Add a ToString() override to source class. Useful if you always want to display the same string for a given class. (Note that the default ToString() is just the class type name, which is why you see "TheProtect.UserControls.Client".)

public class Client
{
    // ...

    public override string ToString()
    {
        return string.Format("{0} ({1})", Name, ID);
    }
}

4) Add a DataTemplate to the XAML resources. This is useful for associating a given class type with a more complex or stylized template.

<UserControl xmlns:local="clr-namespace:TheProject.UserControls">
    <UserControl.Resources>
        <DataTemplate DataType="local:Client">
            <TextBlock Text="{Binding Name}" />
        </DataTemplate>
    </UserControl.Resources>

    // ...

</UserControl>    

Solution 2

In DisplayMemberPath, give the name of the property which you want to show in the comboBox. In SelectedValuePath, give the name of the property which you want to select. When you do a ComboBox.SelectedValue, you will get the value of this property.

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Unrepentent Geek
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Unrepentent Geek

New to this website, new to WPF and C# and handicapped (crippled with life long affliction known as DAAR aka dumb as a rock). Please bear with me.

Updated on July 09, 2022

Comments

  • Unrepentent Geek
    Unrepentent Geek almost 2 years

    Trying to learn how to bind objects to various types of controls. In this instance, I want to get sample data in my object to appear in ComboBox. The code runs but what appears instead of values (David, Helen, Joe) is text "TheProtect.UserControls.Client")

    XAML: (ucDataBindingObject.xaml)

    <UserControl x:Class="TheProject.UserControls.ucDataBindingObject"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                 Width="Auto"
                 Height="Auto"
                 mc:Ignorable="d">
    
        <Grid Width="130"
              Height="240"
              Margin="0">
    
                <ComboBox Width="310"
                          HorizontalAlignment="Left"
                          VerticalAlignment="Top"
                          ItemsSource="{Binding Path=Clients}" />
        </Grid>
    </UserControl>
    

    C#: ucDataBindingObject.xaml.cs

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Windows.Controls;
    namespace TheProject.UserControls
    {
        public partial class ucDataBindingObject : UserControl
        {
    
            public List<Client> Clients { get; set; }
    
    
            public ucDataBindingObject()
            {
                Clients = new List<Client>();
                Clients.Add(new Client(1, "David")); // sample data
                Clients.Add(new Client(2, "Helen"));
                Clients.Add(new Client(3, "Joe"));
    
    
                InitializeComponent();
                this.DataContext = this;
            }
        }
    

    C# Client.cs

    using System;
    using System.Linq;
    
    namespace TheProject.UserControls
    {
        public class Client
        {
            public int ID { get; set; }
            public string Name { get; set; }
    
            public Client(int id, string name)
            {
                this.ID = id;
                this.Name = name;
            }
        }
    }