Kepiye carane nyatakake variabel lan nggunakake var?

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C# iku statically typed — variabel duwe tipe sing dikenal ing wektu compile time. Sampeyan bisa nyatakake variabel kanthi tipe sing eksplisit utawa nggunakake **`var`** kanggo type inference (compiler deduksi tipe saka nilai), nanging cara apa pun tipe kasebut tetep. ## Nyatakake variabel ```csharp int count = 42; // explicit type string name = "Ann"; double price = 9.99; bool active = true; var age = 30; // inferred as int (var = let the compiler figure it out) var message = "Hello"; // inferred as string var items = new List(); // inferred as List ``` `var` nyaraki tipe saka initializer — `var age = 30` pancen padha karo `int age = 30`. Sing penting, **`var` tetep statically typed**: tipe kasebut tetep ing wektu compile time (sampeyan ora bisa nomer ngisor nyumbangake string menyang `age`); iku mung dingarani, ora dinamis. ## var butuh initializer lan tetep tipe ```csharp var x = 5; x = "hi"; // ❌ compile error — x is an int, can't become a string var y; // ❌ error — var needs an initializer to infer from ``` ## Kapan nggunakake var (style) ```csharp var user = new UserService(); // ✅ type is obvious from the right side — var is clean var count = users.Count; int total = CalculateComplexValue(); // explicit when the type isn't obvious aids readability ``` Gunakake `var` nalika tipe iku jelas saka sisi tengen (ngurangi redundansi, utamane karo tipe generik sing dawa); gunakake tipe eksplisit nalika iku nulungi kajehan. ## Konstanta lan nyatakake liyane ```csharp const double Pi = 3.14159; // compile-time constant (can't change) readonly int id; // set once (in constructor), then immutable int a = 1, b = 2; // multiple of the same type nint nativeInt; // platform-sized integer ``` ## Tipe built-in sing umum ```text int, long, short, byte integers float, double, decimal floating point (decimal for money — exact) bool, char, string boolean, character, text object the base of all types ``` ## Kenapa iki penting Nauri nyatakake variabel lan `var` iku pengetahuan C# saben dina sing dhasar. Poin konseptual utama iku yen **`var` iku type inference, dudu dynamic typing** — miskonsepsi sing umum. Karo `var`, compiler deduksi tipe saka initializer, nanging tipe kasebut tetep tetep ing wektu compile time (sampeyan entuk kabeh manfaat static typing — type checking, IntelliSense, performance), mung tanpa nulis jeneng tipe kanthi eksplisit. Iku nggawe `var` dadi kemudahan kanggo kajehan (utamane karo tipe generik sing verbose kaya `Dictionary>`) tinimbang nglongsorake sistem tipe. Nauri kapan nggunakake `var` (nalika tipe iku jelas saka sisi tengen, nyuda redundansi) versus tipe eksplisit (nalika iku nulungi kajehan), bebarengan karo tipe built-in (utamane **`decimal` kanggo dhuwit** — arithmetic decimal sing presisi, ora kaya `double`), konstanta (`const`, `readonly`), iku pengetahuan saben dina kanggo nulis C#. Nauri yen C# iku statically typed saindhi (manah sampeyan nulis tipe utawa nggunakake `var`), lan idiom babagan nyatakake variabel, iku dhasar kanggo maca lan nulis kode C# sing bersih lan bener, lan titik `var`-ora-dinamis iku klarifikasi sing sering banget sing ngandhut pangerten sing leres babagan basa.