Get an Enum Member as a String in C#: .NET 10, generic GetName, format specifiers, custom strings

strings-csharp/EnumMemberAsString/EnumMemberAsString/EnumMemberAsString.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>

strings-csharp/EnumMemberAsString/EnumMemberAsString/classes/Person.cs

@@ -1,13 +1,7 @@
 namespace EnumMemberAsString;
 
-public class Person
+public class Person(string name, Country country)
 {
-    public string Name { get; set; }
-    public Country Country { get; set; }
-
-    public Person(string name, Country country)
-    {
-        Name = name;
-        Country = country;
-    }
+    public string Name { get; set; } = name;
+    public Country Country { get; set; } = country;
 }

strings-csharp/EnumMemberAsString/EnumMemberAsString/classes/Trip.cs

@@ -0,0 +1,7 @@
+namespace EnumMemberAsString;
+
+public class Trip
+{
+    public string Name { get; set; } = string.Empty;
+    public Region Region { get; set; }
+}

strings-csharp/EnumMemberAsString/EnumMemberAsString/enums/Region.cs

@@ -0,0 +1,16 @@
+using System.ComponentModel;
+using System.Runtime.Serialization;
+using System.Text.Json.Serialization;
+
+namespace EnumMemberAsString;
+
+[JsonConverter(typeof(JsonStringEnumConverter))]
+public enum Region
+{
+    [Description("North America")]
+    [EnumMember(Value = "north-america")]
+    NorthAmerica,
+
+    [JsonStringEnumMemberName("asia-pacific")]
+    AsiaPacific,
+}

strings-csharp/EnumMemberAsString/EnumMemberAsStringTests/CustomStringUnitTests.cs

@@ -0,0 +1,33 @@
+using System.ComponentModel;
+using System.Reflection;
+using System.Text.Json;
+
+public class CustomStringUnitTests
+{
+    [Fact]
+    public void WhenMemberHasEnumMemberAttribute_ThenSystemTextJsonIgnoresIt()
+    {
+        var json = JsonSerializer.Serialize(new Trip { Name = "a", Region = Region.NorthAmerica });
+
+        Assert.Equal("{\"Name\":\"a\",\"Region\":\"NorthAmerica\"}", json);
+    }
+
+    [Fact]
+    public void WhenMemberHasJsonStringEnumMemberName_ThenSystemTextJsonUsesIt()
+    {
+        var json = JsonSerializer.Serialize(new Trip { Name = "b", Region = Region.AsiaPacific });
+
+        Assert.Equal("{\"Name\":\"b\",\"Region\":\"asia-pacific\"}", json);
+    }
+
+    [Fact]
+    public void WhenMemberHasDescription_ThenReflectionReturnsIt()
+    {
+        var description = typeof(Region)
+            .GetField(nameof(Region.NorthAmerica))?
+            .GetCustomAttribute<DescriptionAttribute>()?
+            .Description;
+
+        Assert.Equal("North America", description);
+    }
+}

strings-csharp/EnumMemberAsString/EnumMemberAsStringTests/EnumMemberAsStringTests.csproj

@@ -1,21 +1,21 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
 
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.2" />
-    <PackageReference Include="xunit" Version="2.4.2" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.10.1" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="4.0.1">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="coverlet.collector" Version="3.1.2">
+    <PackageReference Include="coverlet.collector" Version="10.1.0">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>

strings-csharp/EnumMemberAsString/EnumMemberAsStringTests/EnumUnitTests.cs

@@ -3,15 +3,25 @@ public class EnumUnitTests
     [Fact]
     public void WhenUsingGetName_ThenReturnsString()
     {
-        var usa = Enum.GetName(typeof(Country), Country.USA);
-        var india = Enum.GetName(typeof(Country), Country.India);
-        var australia = Enum.GetName(typeof(Country), Country.Australia);
+        var usa = Enum.GetName<Country>(Country.USA);
+        var india = Enum.GetName<Country>(Country.India);
+        var australia = Enum.GetName<Country>(Country.Australia);
 
         Assert.Equal("USA", usa);
         Assert.Equal("India", india);
         Assert.Equal("Australia", australia);
     }
 
+    [Fact]
+    public void WhenEnumTypeIsOnlyKnownAtRuntime_ThenGetNameStillReturnsString()
+    {
+        Type enumType = typeof(Country);
+
+        var usa = Enum.GetName(enumType, 0);
+
+        Assert.Equal("USA", usa);
+    }
+
     [Fact]
     public void WhenUsingToString_ThenReturnsString()
     {
@@ -35,4 +45,26 @@ public void WhenUsingNameof_ThenReturnsString()
         Assert.Equal("India", india);
         Assert.Equal("Australia", australia);
     }
-}
+
+    [Fact]
+    public void WhenUsingFormatSpecifiers_ThenReturnsExpectedText()
+    {
+        var country = Country.Australia;
+
+        Assert.Equal("Australia", country.ToString("G"));
+        Assert.Equal("2", country.ToString("D"));
+        Assert.Equal("00000002", country.ToString("X"));
+        Assert.Equal("Australia", country.ToString("F"));
+        Assert.Equal("0", Country.USA.ToString("D"));
+        Assert.Equal("00000000", Country.USA.ToString("X"));
+    }
+
+    [Fact]
+    public void WhenValueIsNotDefined_ThenGetNameIsNullAndToStringIsTheNumber()
+    {
+        var undefined = (Country)20;
+
+        Assert.Null(Enum.GetName<Country>(undefined));
+        Assert.Equal("20", undefined.ToString());
+    }
+}

strings-csharp/EnumMemberAsString/EnumMemberAsStringTests/InstanceUnitTests.cs

@@ -7,9 +7,9 @@ public class InstanceUnitTests
     [Fact]
     public void WhenUsingGetName_ThenReturnsString()
     {
-        var usa = Enum.GetName(typeof(Country), bob.Country);
-        var india = Enum.GetName(typeof(Country), alice.Country);
-        var australia = Enum.GetName(typeof(Country), john.Country);
+        var usa = Enum.GetName<Country>(bob.Country);
+        var india = Enum.GetName<Country>(alice.Country);
+        var australia = Enum.GetName<Country>(john.Country);
 
         Assert.Equal("USA", usa);
         Assert.Equal("India", india);