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CSharp · Console

/Program.cs

using System;
using System.Linq;

public class Program
{
	public static void Main()
	{
		var input = @"[""gm-63.pdf"",""GM413.pdf"",""mh524.pdf""]";
		var result = input.Trim('[', ']').Split(new[]{','}).Select(x => x.Trim('"')).ToArray();
		foreach (var item in result)
			Console.WriteLine(item);
	}
}