// C# Extension Method
// Doc: https://csharp-extension.com/en/method/1002063/string-notin
// @nuget: Z.ExtensionMethods
using System;
public class Program
{
public static void Main()
string [] values = {"EntityFramework", " ", "SQL", "", "Java", null};
string newValue = "Dapper";
// C# Extension Method: String - NotIn
if(newValue.NotIn(values))
Console.WriteLine("String: {0}", newValue);
}