المطابقة النمطية (Pattern Matching)

object value = 42;

if (value is int number)
{
    Console.WriteLine($"عدد صحيح: {number}");
}

string Grade(int score) => score switch
{
    >= 90 => "ممتاز",
    >= 75 => "جيد جدًا",
    >= 60 => "مقبول",
    _     => "راسب"
};

class Order
{
    public decimal Total;
    public string Country = "";
}

string ShippingFee(Order o) => o switch
{
    { Country: "SA", Total: >= 200 } => "شحن مجاني",
    { Country: "SA" }                => "15 ريال",
    { Total: >= 200 }                => "شحن مجاني دولي",
    _                                 => "25 ريال"
};

string Classify(int x) => x switch
{
    int n when n < 0  => "سالب",
    0                  => "صفر",
    int n when n % 2 == 0 => "زوجي موجب",
    _                  => "فردي موجب"
};

bool IsVowel(char c) => c is 'a' or 'e' or 'i' or 'o' or 'u';

bool InRange(int n) => n is >= 1 and <= 100;

bool NotNull(object? o) => o is not null;