public class MyInfo
{
    public string Name { get; set; }
    public double Diff { get; set; }
    public string File { get; set; }
}

static void Main(string[] args)
{
    PSObject obj = PSObject.AsPSObject(new { Name = "David", Diff = 0.2, File = "output.txt" });

    var serialized = JsonConvert.SerializeObject(obj.Properties.ToDictionary(k => k.Name, v => v.Value));
    Console.WriteLine(serialized);

    var deseialized = JsonConvert.DeserializeObject<MyInfo>(serialized);
    Console.WriteLine($"Name: {deseialized.Name}");
    Console.WriteLine($"Diff: {deseialized.Diff}");
    Console.WriteLine($"File: {deseialized.File}");
}