How to bind an enum to a combobox control in WPF?

You can do it from code by placing the following code in Window Loaded event handler, for example:

yourComboBox.ItemsSource = Enum.GetValues(typeof(EffectStyle)).Cast<EffectStyle>();

If you need to bind it in XAML you need to use ObjectDataProvider to create object available as binding source:

<Window x:Class="YourNamespace.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:System="clr-namespace:System;assembly=mscorlib"
        xmlns:StyleAlias="clr-namespace:Motion.VideoEffects">
    <Window.Resources>
        <ObjectDataProvider x:Key="dataFromEnum" MethodName="GetValues"
                            ObjectType="{x:Type System:Enum}">
            <ObjectDataProvider.MethodParameters>
                <x:Type TypeName="StyleAlias:EffectStyle"/>
            </ObjectDataProvider.MethodParameters>
        </ObjectDataProvider>
    </Window.Resources>
    <Grid>
        <ComboBox ItemsSource="{Binding Source={StaticResource dataFromEnum}}"
                  SelectedItem="{Binding Path=CurrentEffectStyle}" />
    </Grid>
</Window>

Draw attention on the next code:

xmlns:System="clr-namespace:System;assembly=mscorlib"
xmlns:StyleAlias="clr-namespace:Motion.VideoEffects"

Guide how to map namespace and assembly you can read on MSDN.

I like for all objects that I'm binding to be defined in my ViewModel, so I try to avoid using <ObjectDataProvider> in the xaml when possible.

My solution uses no data defined in the View and no code-behind. Only a DataBinding, a reusable ValueConverter, a method to get a collection of descriptions for any Enum type, and a single property in the ViewModel to bind to.

When I want to bind an Enum to a ComboBox the text I want to display never matches the values of the Enum, so I use the [Description()] attribute to give it the text that I actually want to see in the ComboBox. If I had an enum of days of the week, it would look something like this:

public enum DayOfWeek
{
  // add an optional blank value for default/no selection
  [Description("")]
  NOT_SET = 0,
  [Description("Sunday")]
  SUNDAY,
  [Description("Monday")]
  MONDAY,
  ...
}

First I created helper class with a couple methods to deal with enums. One method gets a description for a specific value, the other method gets all values and their descriptions for a type.

public static class EnumHelper
{
  public static string Description(this Enum value)
  {
    var attributes = value.GetType().GetField(value.ToString()).GetCustomAttributes(typeof(DescriptionAttribute), false);
    if (attributes.Any())
      return (attributes.First() as DescriptionAttribute).Description;

    // If no description is found, the least we can do is replace underscores with spaces
    // You can add your own custom default formatting logic here
    TextInfo ti = CultureInfo.CurrentCulture.TextInfo;
    return ti.ToTitleCase(ti.ToLower(value.ToString().Replace("_", " ")));
  }

  public static IEnumerable<ValueDescription> GetAllValuesAndDescriptions(Type t)
  {
    if (!t.IsEnum)
      throw new ArgumentException($"{nameof(t)} must be an enum type");

    return Enum.GetValues(t).Cast<Enum>().Select((e) => new ValueDescription() { Value = e, Description = e.Description() }).ToList();
  }
}

Next, we create a ValueConverter. Inheriting from MarkupExtension makes it easier to use in XAML so we don't have to declare it as a resource.

[ValueConversion(typeof(Enum), typeof(IEnumerable<ValueDescription>))]
public class EnumToCollectionConverter : MarkupExtension, IValueConverter
{
  public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
  {
    return EnumHelper.GetAllValuesAndDescriptions(value.GetType());
  }
  public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
  {
    return null;
  }
  public override object ProvideValue(IServiceProvider serviceProvider)
  {
    return this;
  }
}

My ViewModel only needs 1 property that my View can bind to for both the SelectedValue and ItemsSource of the combobox:

private DayOfWeek dayOfWeek;

public DayOfWeek SelectedDay
{
  get { return dayOfWeek; }
  set
  {
    if (dayOfWeek != value)
    {
      dayOfWeek = value;
      OnPropertyChanged(nameof(SelectedDay));
    }
  }
}

And finally to bind the ComboBox view (using the ValueConverter in the ItemsSource binding)...

<ComboBox ItemsSource="{Binding Path=SelectedDay, Converter={x:EnumToCollectionConverter}, Mode=OneTime}"
          SelectedValuePath="Value"
          DisplayMemberPath="Description"
          SelectedValue="{Binding Path=SelectedDay}" />

To implement this solution you only need to copy my EnumHelper class and EnumToCollectionConverter class. They will work with any enums. Also, I didn't include it here, but the ValueDescription class is just a simple class with 2 public object properties, one called Value, one called Description. You can create that yourself or you can change the code to use a Tuple<object, object> or KeyValuePair<object, object>

I used another solution using MarkupExtension.

I made class which provides items source:

public class EnumToItemsSource : MarkupExtension
{
    private readonly Type _type;

    public EnumToItemsSource(Type type)
    {
        _type = type;
    }

    public override object ProvideValue(IServiceProvider serviceProvider)
    {
        return Enum.GetValues(_type)
            .Cast<object>()
            .Select(e => new { Value = (int)e, DisplayName = e.ToString() });
    }
}

That's almost all... Now use it in XAML:

    <ComboBox DisplayMemberPath="DisplayName"
          ItemsSource="{persons:EnumToItemsSource {x:Type enums:States}}"
          SelectedValue="{Binding Path=WhereEverYouWant}"
          SelectedValuePath="Value" />

Change 'enums:States' to your enum

How to bind an enum to a combobox control in WPF?

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