There are times when it is necessary to check if the constant name or numeric value is defined in the Enum . We can use the Enum.IsDefined method to verify this.
How to Check if the Enum Value is Defined in C# ?
Below is a sample code to demonstrate how to Check if the Enum Value is Defined in C# using Enum.IsDefined method. The Enum.IsDefined takes either the constant name or integer value as its second parameter which is shown in the below code snippet.
internal enum ProgrammingLanguages
{
CSharp,
Java = 1,
Erlang = 2,
Delphi = 3,
PHP
}
public partial class Form1 : Form
{
private void Form1_Load(object sender, EventArgs e)
{
// Using Constant
if (!Enum.IsDefined(typeof(ProgrammingLanguages), "Objective-C"))
MessageBox.Show("This language is not defined.");
// Using Integer
if (!Enum.IsDefined(typeof(ProgrammingLanguages), 22))
MessageBox.Show("This language is not defined.");
}
}