C# - Enum.GetName, GetNames: Get String Array From Enum

Enum.GetName. An enum type has names. These names are string representations of the enum values. The .NET Framework provides the Enum.GetName and Enum.GetNames methods.

Method notes. These methods require the typeof operator. They return a string or a string array. With GetNames, we can get many names at once.

enum

enum ToString

GetName example. The first argument to the Enum.GetName method is a Type. And this is easily provided with the result of the typeof operator.

And The second argument is an object: this object must be of the same type as the backing field for the enum.

Here An int is provided (with the value 3) and the correct MedicationType is returned.

typeof

using System; class Program { enum MedicationType { Default, Antipyretic, Corticosteroid, Cytotoxic, Decongestant, Expectorant }; static void Main() { string name = Enum.GetName(typeof(MedicationType), MedicationType.Cytotoxic); Console.WriteLine(name); name = Enum.GetName(typeof(MedicationType), 3); Console.WriteLine(name); } }

Cytotoxic Cytotoxic

Enum.GetNames. This method also requires the Type pointer. This means you can pass it the typeof(Identifier) where Identifier is the identifier for your enumerated type.

Type

Tip The typeof operator invokes reflection and the Enum.GetNames method also internally accesses the metadata representation in memory.

Next This program shows how an enumerated type of medication types is accessed in a string array.

Detail Here Enum.GetNames() is invoked. Enum.GetNames does not use an instance of an enumeration to be called.

Detail This is a static method. We pass it a Type object as the parameter. The typeof expression returns that Type object.

static

using System; class Program { enum MedicationType { Default, Antipyretic, Corticosteroid, Cytotoxic, Decongestant, Expectorant }; static void Main() { // Get all enum names as strings. var names = Enum.GetNames(typeof(MedicationType)); // Write the enum names separated by a space. Console.WriteLine(string.Join(" ", names)); } }

Default Antipyretic Corticosteroid Cytotoxic Decongestant Expectorant

Performance. GetName has internal checks that will reduce performance. If you are calling Enum.GetName in a tight loop, using a cache or finding another approach would be beneficial.

Typeof parameter. The typeof operator also uses a parameter, but the parameter is a Type identifier. The MedicationType identifier is the name of the enum and not an instance of the enum.

Reflection

Detail The typeof operator is a simple usage of reflection in that it accesses the program's metadata information.

A summary. The Enum.GetName() method provides a way to get one string value based on an object value. It requires a type pointer.

Summary, continued. GetNames() returns the entire collection of string representations at once. If you need to use enum names repeatedly, consider storing them as a string array or list.

String List