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CSharp · Console

/Program.cs

using System;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		var items = new Data[] { new Data { A = "one"} };
		
		string[] newData = items
			.Select(i => i.A += "!")
			.ToArray();
		
		foreach (var d in newData)
		{
			Console.WriteLine(d);	
		}
	}
}

public class Data
{
	public string A {get;set;}
}