SOLUTION: int enumValue = 2; // The value for which you want to get string string enumName = Enum. GetName(typeof(EnumDisplayStatus), enumValue);
The MVC framework sees the enum value as a simple primitive and uses the default string template. One solution to change the default framework behavior is to write a custom model metadata provider and implement GetMetadataForProperty to use a template with the name of "Enum" for such models.
To get the value of enum we can simply typecast it to its type. In the first example, the default type is int so we have to typecast it to int. Also, we can get the string value of that enum by using the ToString() method as below.
One liner - Fluent syntax
public static class Extensions
{
/// <summary>
/// A generic extension method that aids in reflecting
/// and retrieving any attribute that is applied to an `Enum`.
/// </summary>
public static TAttribute GetAttribute<TAttribute>(this Enum enumValue)
where TAttribute : Attribute
{
return enumValue.GetType()
.GetMember(enumValue.ToString())
.First()
.GetCustomAttribute<TAttribute>();
}
}
Example
public enum Season
{
[Display(Name = "It's autumn")]
Autumn,
[Display(Name = "It's winter")]
Winter,
[Display(Name = "It's spring")]
Spring,
[Display(Name = "It's summer")]
Summer
}
public class Foo
{
public Season Season = Season.Summer;
public void DisplayName()
{
var seasonDisplayName = Season.GetAttribute<DisplayAttribute>();
Console.WriteLine("Which season is it?");
Console.WriteLine (seasonDisplayName.Name);
}
}
Which season is it?
It's summer
UPDATE
First solution was focused on getting display names from enum. Code below should be exact solution for your problem.
You can use this helper class for enums:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;
public static class EnumHelper<T>
where T : struct, Enum // This constraint requires C# 7.3 or later.
{
public static IList<T> GetValues(Enum value)
{
var enumValues = new List<T>();
foreach (FieldInfo fi in value.GetType().GetFields(BindingFlags.Static | BindingFlags.Public))
{
enumValues.Add((T)Enum.Parse(value.GetType(), fi.Name, false));
}
return enumValues;
}
public static T Parse(string value)
{
return (T)Enum.Parse(typeof(T), value, true);
}
public static IList<string> GetNames(Enum value)
{
return value.GetType().GetFields(BindingFlags.Static | BindingFlags.Public).Select(fi => fi.Name).ToList();
}
public static IList<string> GetDisplayValues(Enum value)
{
return GetNames(value).Select(obj => GetDisplayValue(Parse(obj))).ToList();
}
private static string lookupResource(Type resourceManagerProvider, string resourceKey)
{
var resourceKeyProperty = resourceManagerProvider.GetProperty(resourceKey,
BindingFlags.Static | BindingFlags.Public, null, typeof(string),
new Type[0], null);
if (resourceKeyProperty != null)
{
return (string)resourceKeyProperty.GetMethod.Invoke(null, null);
}
return resourceKey; // Fallback with the key name
}
public static string GetDisplayValue(T value)
{
var fieldInfo = value.GetType().GetField(value.ToString());
var descriptionAttributes = fieldInfo.GetCustomAttributes(
typeof(DisplayAttribute), false) as DisplayAttribute[];
if (descriptionAttributes[0].ResourceType != null)
return lookupResource(descriptionAttributes[0].ResourceType, descriptionAttributes[0].Name);
if (descriptionAttributes == null) return string.Empty;
return (descriptionAttributes.Length > 0) ? descriptionAttributes[0].Name : value.ToString();
}
}
And then you can use it in your view as following:
<ul>
@foreach (var value in @EnumHelper<UserPromotion>.GetValues(UserPromotion.None))
{
if (value == Model.JobSeeker.Promotion)
{
var description = EnumHelper<UserPromotion>.GetDisplayValue(value);
<li>@Html.DisplayFor(e => description )</li>
}
}
</ul>
Hope it helps! :)
Building on Aydin's great answer, here's an extension method that doesn't require any type parameters.
using System;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;
public static class EnumExtensions
{
public static string GetDisplayName(this Enum enumValue)
{
return enumValue.GetType()
.GetMember(enumValue.ToString())
.First()
.GetCustomAttribute<DisplayAttribute>()
.GetName();
}
}
NOTE: GetName() should be used instead of the Name property. This ensures that the localized string will be returned if using the ResourceType attribute property.
Example
To use it, just reference the enum value in your view.
@{
UserPromotion promo = UserPromotion.SendJobOffersByMail;
}
Promotion: @promo.GetDisplayName()
Output
Promotion: Send Job Offers By Mail
Based on Aydin's answer I would suggest a less "duplicatious" implementation (because we could easily get the Type
from the Enum
value itself, instead of providing it as a parameter 😉:
using System;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;
public static string GetDisplayName(this Enum enumValue)
{
return enumValue.GetType().GetMember(enumValue.ToString())
.First()
.GetCustomAttribute<DisplayAttribute>()
.Name;
}
EDIT (based upon @Vahagn Nahapetyan's comment)
public static string GetDisplayName(this Enum enumValue)
{
return enumValue.GetType()?
.GetMember(enumValue.ToString())?
.First()?
.GetCustomAttribute<DisplayAttribute>()?
.Name;
}
Now we can use it very clean in this way:
public enum Season
{
[Display(Name = "The Autumn")]
Autumn,
[Display(Name = "The Weather")]
Winter,
[Display(Name = "The Tease")]
Spring,
[Display(Name = "The Dream")]
Summer
}
Season.Summer.GetDisplayName();
Which results in
"The Dream"
If you are using MVC 5.1 or upper there is simplier and clearer way: just use data annotation (from System.ComponentModel.DataAnnotations
namespace) like below:
public enum Color
{
[Display(Name = "Dark red")]
DarkRed,
[Display(Name = "Very dark red")]
VeryDarkRed,
[Display(Name = "Red or just black?")]
ReallyDarkRed
}
And in view, just put it into proper html helper:
@Html.EnumDropDownListFor(model => model.Color)
Building on Todd's great answer which built on Aydin's great answer, here's a generic extension method which doesn't require any type parameters.
/// <summary>
/// Gets human-readable version of enum.
/// </summary>
/// <returns>effective DisplayAttribute.Name of given enum.</returns>
public static string GetDisplayName<T>(this T enumValue) where T : IComparable, IFormattable, IConvertible
{
if (!typeof(T).IsEnum)
throw new ArgumentException("Argument must be of type Enum");
DisplayAttribute displayAttribute = enumValue.GetType()
.GetMember(enumValue.ToString())
.First()
.GetCustomAttribute<DisplayAttribute>();
string displayName = displayAttribute?.GetName();
return displayName ?? enumValue.ToString();
}
I needed this for my project because something like the below code, where not every member of the enum has a DisplayAttribute
, throws an exception with Todd's solution:
public class MyClass
{
public enum MyEnum
{
[Display(Name="ONE")]
One,
// No DisplayAttribute
Two
}
public void UseMyEnum()
{
MyEnum foo = MyEnum.One;
MyEnum bar = MyEnum.Two;
Console.WriteLine(foo.GetDisplayName());
Console.WriteLine(bar.GetDisplayName());
}
}
// Output:
//
// ONE
// Two
If this is a complicated solution to a simple problem, please let me know, but this was the fix I used.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With