using System;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
String miRuta = "C:\\Users\\JoseCarlos\\Desktop\\mv\\lolo-s001.vmdk";
Console.WriteLine(miRuta);
Console.WriteLine(Regex.Replace(miRuta, "[^\\\\]+(?=\\\\[^\\\\]+$)", "lolo"));
}
}
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