Fayllar va JSON

string yol = Path.Combine(Path.GetTempPath(), "sinov.txt");

File.WriteAllText(yol, "Birinchi qator\nIkkinchi qator");

string matn = File.ReadAllText(yol);
Console.WriteLine($"O'qildi ({matn.Length} belgi):");
Console.WriteLine(matn);

File.Delete(yol);
Console.WriteLine($"Fayl mavjudmi: {File.Exists(yol)}");

string yol = Path.Combine(Path.GetTempPath(), "shaharlar.txt");

File.WriteAllLines(yol, ["Namangan", "Andijon", "Samarqand"]);

string[] qatorlar = File.ReadAllLines(yol);
Console.WriteLine($"{qatorlar.Length} ta qator:");

for (int i = 0; i < qatorlar.Length; i++)
{
    Console.WriteLine($"  {i + 1}. {qatorlar[i]}");
}

File.AppendAllText(yol, "Toshkent\n");
Console.WriteLine($"Qo'shilgandan keyin: {File.ReadAllLines(yol).Length} ta");

File.Delete(yol);

string yol = Path.Combine("hujjatlar", "hisobot", "2026-yil.txt");

Console.WriteLine($"To'liq yo'l:  {yol}");
Console.WriteLine($"Fayl nomi:    {Path.GetFileName(yol)}");
Console.WriteLine($"Kengaytmasiz: {Path.GetFileNameWithoutExtension(yol)}");
Console.WriteLine($"Kengaytma:    {Path.GetExtension(yol)}");
Console.WriteLine($"Papka:        {Path.GetDirectoryName(yol)}");
Console.WriteLine($"Almashtirish: {Path.ChangeExtension(yol, ".pdf")}");

string asos = Path.Combine(Path.GetTempPath(), "sinovkatalog");
string ichki = Path.Combine(asos, "ichki");

Directory.CreateDirectory(ichki);

File.WriteAllText(Path.Combine(asos, "a.txt"), "a");
File.WriteAllText(Path.Combine(asos, "b.txt"), "b");
File.WriteAllText(Path.Combine(ichki, "c.txt"), "c");

Console.WriteLine($"Faqat asosda:  {Directory.GetFiles(asos).Length} ta");
int hammasi = Directory
    .GetFiles(asos, "*", SearchOption.AllDirectories).Length;
Console.WriteLine($"Ichkisi bilan: {hammasi} ta");
Console.WriteLine(
    $"Papkalar:      {Directory.GetDirectories(asos).Length} ta");

Directory.Delete(asos, recursive: true);
Console.WriteLine($"Katalog mavjudmi: {Directory.Exists(asos)}");

using System.Text.Json;

var talaba = new Talaba("Husanboy Qodirov", 25,
    ["Informatika", "Matematika"]);

string json = JsonSerializer.Serialize(talaba, new JsonSerializerOptions
{
    WriteIndented = true
});

Console.WriteLine(json);

record Talaba(string Ism, int Yosh, string[] Fanlar);

using System.Text.Json;

string json = """
    {
      "Ism": "Malika Tursunova",
      "Yosh": 20,
      "Fanlar": ["Fizika", "Kimyo"]
    }
    """;

Talaba? t = JsonSerializer.Deserialize<Talaba>(json);

if (t is not null)
{
    Console.WriteLine($"{t.Ism}, {t.Yosh} yosh");
    Console.WriteLine($"Fanlari: {string.Join(", ", t.Fanlar)}");
}

record Talaba(string Ism, int Yosh, string[] Fanlar);

using System.Text.Json;

string yol = Path.Combine(Path.GetTempPath(), "talabalar.json");

List<Talaba> royxat =
[
    new("Husanboy", 92),
    new("Malika", 78),
    new("Nodira", 85)
];

File.WriteAllText(yol, JsonSerializer.Serialize(royxat));

var oqilgan =
    JsonSerializer.Deserialize<List<Talaba>>(File.ReadAllText(yol)) ?? [];

Console.WriteLine($"Saqlandi va o'qildi: {oqilgan.Count} ta");
Console.WriteLine($"O'rtacha ball: {oqilgan.Average(t => t.Ball):F1}");
Console.WriteLine($"Eng yuqori: {oqilgan.MaxBy(t => t.Ball)?.Ism}");

File.Delete(yol);

record Talaba(string Ism, int Ball);

using System.Text.Encodings.Web;
using System.Text.Json;
using System.Text.Json.Serialization;

var talaba = new Talaba("Husanboy", null);

Console.WriteLine("Sukut bo'yicha:");
Console.WriteLine(JsonSerializer.Serialize(talaba));

Console.WriteLine("\nO'zbek harflari va null siz:");
Console.WriteLine(JsonSerializer.Serialize(
    new Talaba("Farg'ona", null),
    new JsonSerializerOptions
    {
        Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping,
        DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
    }));

record Talaba(string Ism, string? Izoh);