Introduction to Dart More Basic To Advance

Flutter development seekhne ke liye hum basic se start karenge aur dheere-dheere advance topics tak pahuchenge. Main aapko

1. Variables and Functions

Variables: Yeh data ko store karne ke liye use hoti hain. Dart me, variables ko declare karne ke liye var, int, double, String etc. use karte hain.

var name = 'John';
int age = 25;
double height = 5.9;
        

Functions: Yeh reusable code blocks hain jo specific task perform karte hain.

void greet() {
  print('Hello!');
}

int add(int a, int b) {
  return a + b;
}
        

2. Decision Making and Loops

Decision Making: Dart me decision making ke liye if, else if, aur else use hota hai.

int age = 20;
if (age > 18) {
  print('Adult');
} else {
  print('Not an Adult');
}
        

Loops: Repeat tasks karne ke liye loops use hote hain jaise for, while, do-while.

for (int i = 0; i < 5; i++) {
  print(i);
}

int count = 0;
while (count < 5) {
  print(count);
  count++;
}
        

3. Strings

Strings text ko represent karte hain. Aap single ya double quotes use karke strings bana sakte hain.

String greeting = 'Hello';
String name = "Alice";
String message = 'Hello, $name!'; // String interpolation
        

4. More Advance Dart

Isme aapko Dart ke kuch advance concepts jaise async programming, collections (List, Set, Map), futures, streams etc. samajhne padenge.

List: Ordered collection hai.

List<int> numbers = [1, 2, 3, 4];
        

Map: Key-value pairs hoti hain.

Map<String, int> ages = {'Alice': 25, 'Bob': 30};
        

5. Continue and Break

Loops me continue aur break use hota hai to control the flow.

for (int i = 0; i < 5; i++) {
  if (i == 2) continue; // Skip this iteration
  if (i == 4) break; // Exit the loop
  print(i);
}
        

6. Final and Const Keyword

Final: Run-time constant hai, value assign hone ke baad change nahi ho sakti.

final name = 'John';
        

Const: Compile-time constant hai, aur ye value compile hone ke time pe hi fix ho jati hai.

const pi = 3.14;
        

7. Object-Oriented Programming

OOP concepts jaise classes, objects, inheritance, polymorphism Dart me important hain.

class Animal {
  String name;

  Animal(this.name);

  void speak() {
    print('$name makes a sound');
  }
}

class Dog extends Animal {
  Dog(String name) : super(name);

  @override
  void speak() {
    print('$name barks');
  }
}

void main() {
  Dog dog = Dog('Rex');
  dog.speak(); // Rex barks
}
        

8. Exception Handlings

Exceptions unexpected errors ko handle karne me help karti hain.

dart

try {
  int result = 10 ~/ 0;
} catch (e) {
  print('Error: $e');
} finally {
  print('This will always execute');
}
        

9. Understand Flutter IDE

Flutter development ke liye aapko IDE (Integrated Development Environment) jaise Android Studio ya Visual Studio Code ka use karna hoga. IDE me aap Flutter plugins install kar sakte hain jo development ko easy banata hai. Aap yahan project create, debug aur run kar sakte hain.

Ab aapko in topics ke baare me kuch idea ho gaya hoga. Flutter me practice aur projects banake aap apni skills ko aur enhance kar sakte hain. Happy coding!