1/100DaysOfFlutter : Dart Basics - Final v/s Const

#flutter #dart #tutorial #codenewbie

1/100DaysOfFlutter : Dart Basics/Final v/s Const

Variables in dart

var: variable can be reassigned.
final: variable can not be reassigned.
const: constant variable.

Different between Final and Const

in a easy way

final name;✅
// you assign value of final after declaration.
name = 'Dart'; ✅

// NOT POSSIBLE WITH DART
const pi;❌
// ERROR: cannot initialize const variable, assign a value to it.
const pi = 3.14;✅

How dart code starts;

void main() {
  print('Hello World');
}

in dart code, the Main function is the entry point of the program

1. You wan to print something on the console; start with main().
2. You want to return something; start with main().
3. main() is starting.

What is dart?

Dart is Static language; which meaning everything thing should have a type.
Name, Place, Animal, things
any things/ everything should have a type.

String name = 10;
int age = 10;

print in dart.

print('1/100DaysOfFlutter : Dart Basics');

String Interpolation in dart

this feature helps us to use variables in dart

void main(){
    String name = 'Dart';
    print("Hello $name");
}

Taking input in console.


import 'dart:io';

void main(){
    stdout.write('Enter your name: ');
    String? name = stdin.readLineSync();
    // currently ignore "?"
    print('Hello $name');
}

Data Types 🙈🙉🙊🐵 in dart:

Number: int, double, num
String : String
Boolean: bool (True or False)
List: List (Array)
Map: Map (Dictionary/ Object)
Null: null
Dynamic: fancyname
Void: void/nothing⛔
Function: Function/🤖