Binding enum type to textbox
I bind textbox.text value to enum type. My enum looks like that
public enum Type
{
Active,
Selected,
ActiveAndSelected
}
What I wan't to acomplish is to show on textbox "Active Mode" instead of "Active" and so on. Is it possible to do that? It would be 开发者_StackOverflow社区great if I could acomplish that in XAML - because all bindings I have in style file style.xaml
I was trying to use Description attributes but it seems that it's not enough
IMHO, using a converter is a better approach.
The first thing you should do is implement a simple attribute in order to add some metadata to your enum elements. Here's a basic example (without internationalization for simplicity):
public enum StepStatus {
[StringValue("Not done yet")]
NotDone,
[StringValue("In progress")]
InProgress,
[StringValue("Failed")]
Failed,
[StringValue("Succeeded")]
Succeeded
}
Next to that, you can write a utility class able to convert from an enum element to its corresponding StringValue representation using reflection. Search in Google for "String Enumerations in C# - CodeProject" and you'll find CodeProject's article about this (sorry, my low reputation won't let me add the link..)
Now you can implement a converter that simply delegates the conversion to the utility class:
[ValueConversion(typeof(StepStatus), typeof(String))]
public class StepStatusToStringConverter: IValueConverter {
public object Convert(object value, Type targetType, object parameter, CultureInfo culture){
String retVal = String.Empty;
if (value != null && value is StepStatus) {
retVal = StringEnum.GetStringValue((StepStatus)value);
}
return retVal;
}
/// <summary>
/// ConvertBack value from binding back to source object. This isn't supported.
/// </summary>
public object ConvertBack(object value, Type targetType,
object parameter, CultureInfo culture) {
throw new Exception("Can't convert back");
}
}
Finally, you can use the converter in your XAML code:
<resourceWizardConverters:StepStatusToStringConverter x:Key="stepStatusToStringConverter" />
...
<TextBox Text="{Binding Path=ResourceCreationRequest.ResourceCreationResults.ResourceCreation, Converter={StaticResource stepStatusToStringConverter}}" ... />
Check the following page; it gives an example that supports internationalization, but basically the principle is the same..
You do not need a converter for this simple case. Use Stringformat in stead. The leading '{}' are an escape sequence to tell the parser that you do not mean to use them for another nested tag. If you add text before the bound text (indicated by '{0}'), you can remove them.
<Window x:Class="TextBoxBoundToEnumSpike.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<StackPanel>
<TextBox Text="{Binding ModeEnum,StringFormat={}{0} Mode}"/>
<Button Click="Button_Click" Height=" 50">
Change to 'Selected'
</Button>
</StackPanel>
</Window>
using System.ComponentModel;
using System.Windows;
namespace TextBoxBoundToEnumSpike
{
public partial class MainWindow : Window,INotifyPropertyChanged
{
private ModeEnum m_modeEnum;
public MainWindow()
{
InitializeComponent();
DataContext = this;
ModeEnum = ModeEnum.ActiveAndSelected;
}
public ModeEnum ModeEnum
{
set
{
m_modeEnum = value;
if (PropertyChanged!=null)PropertyChanged(this,new PropertyChangedEventArgs("ModeEnum"));
}
get { return m_modeEnum; }
}
public event PropertyChangedEventHandler PropertyChanged;
private void Button_Click(object sender, RoutedEventArgs e)
{
ModeEnum = ModeEnum.Selected;
}
}
public enum ModeEnum
{
Active,
Selected,
ActiveAndSelected
}
}
You can use a Converter to do this. Bind to the enum normally but add a Converter property to the binding. The converter is a class implementing IValueConverter, which will be called by WPF. There, you can add a suffix like "Mode" (or do whatever you like).
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