Dart Hello World

Introduction to Dart

Dart is an open-source, general-purpose programming language developed by Google. It was first unveiled in 2011 and has gained popularity as a language for building web, mobile, and desktop applications. Dart is designed to be fast, efficient, and easy to learn.

History

Dart was created by Google as an alternative to JavaScript for building web applications. It was initially intended as a replacement for JavaScript in the browser, but it has evolved into a versatile language that can be used for a wide range of applications.

The first version, called Dart 1.0, was released in November 2013. Since then, Dart has gone through several major releases, with the latest stable release being Dart 2.10. Dart is also the language used for developing applications with the Flutter framework, which is widely used for building cross-platform mobile apps.

Features

Dart comes with a number of features that make it a powerful and flexible programming language:

Strong Typing: Dart is a statically-typed language, which means that variables are explicitly declared with their types. This helps catch errors at compile-time and makes the code more reliable.
Garbage Collection: Dart uses automatic garbage collection to manage memory, allowing developers to focus on writing code rather than memory management.
Asynchronous Programming: Dart has built-in support for asynchronous programming, making it easy to write code that performs non-blocking operations. This is particularly useful for building web applications that need to handle multiple concurrent requests.
Object-Oriented: Dart is an object-oriented language, which means that it supports concepts such as classes, objects, inheritance, and polymorphism. This makes it easy to organize code into reusable and modular components.
Interoperability: Dart can be used alongside JavaScript, allowing developers to reuse existing JavaScript code or libraries in their Dart applications. This makes it easy to integrate Dart into existing projects.

Hello World in Dart

To get started with Dart, let's write a simple "Hello World" program. Here are the steps:

Install Dart: Visit the official Dart website at dart.dev and follow the instructions to install Dart on your operating system.
Set up a Dart project: Open your preferred code editor and create a new directory for your Dart project. Inside the directory, create a new file called hello.dart.
Write the code: Open the hello.dart file and enter the following code:

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

Run the program: Open your terminal or command prompt, navigate to the directory where the hello.dart file is located, and run the following command:

dart hello.dart

You should see the output Hello, World! printed in the terminal.

Examples

Example 1: Hello, World!

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

Expected Output:

Hello, World!

Explanation:

void main() is the entry point of a Dart program.
print() is a built-in function that displays the specified message on the console.

Example 2: Variables and Data Types

void main() {
  String name = 'John';
  int age = 25;
  double height = 1.75;
  bool isStudent = true;

  print('Name: $name');
  print('Age: $age');
  print('Height: $height');
  print('Is Student: $isStudent');
}

Expected Output:

Name: John
Age: 25
Height: 1.75
Is Student: true

Explanation:

Dart supports various data types such as String, int, double, and bool.
The $ symbol is used for string interpolation to include variable values within a string.

Example 3: Arithmetic Operations

void main() {
  int a = 5;
  int b = 3;

  int sum = a + b;
  int difference = a - b;
  int product = a * b;
  double quotient = a / b;
  int remainder = a % b;

  print('Sum: $sum');
  print('Difference: $difference');
  print('Product: $product');
  print('Quotient: $quotient');
  print('Remainder: $remainder');
}

Expected Output:

Sum: 8
Difference: 2
Product: 15
Quotient: 1.6666666666666667
Remainder: 2

Explanation:

Basic arithmetic operations like addition (+), subtraction (-), multiplication (*), division (/), and modulo (%) can be performed in Dart.

Example 4: Conditional Statements

void main() {
  int age = 19;

  if (age >= 18) {
    print('You are eligible to vote.');
  } else {
    print('You are not eligible to vote.');
  }
}

Expected Output:

You are eligible to vote.

Explanation:

Conditional statements like if and else help control the flow of execution based on certain conditions.
If the condition (age >= 18) is true, the code inside the if block will be executed; otherwise, the code inside the else block will be executed.

Example 5: Loops

void main() {
  for (int i = 1; i <= 5; i++) {
    print(i);
  }
}

Expected Output:

Explanation:

The for loop allows you to repeat a block of code for a specific number of times or until a condition is met.
In this example, the loop iterates from 1 to 5, incrementing the variable i by 1 in each iteration.

Example 6: Lists

void main() {
  List<String> fruits = ['Apple', 'Banana', 'Orange'];

  for (String fruit in fruits) {
    print(fruit);
  }
}

Expected Output:

Apple
Banana
Orange

Explanation:

Lists are used to store multiple values in Dart.
In this example, we define a list of strings named fruits and iterate over each element using a for-in loop.

Example 7: Functions

void main() {
  int result = multiply(5, 3);
  print('Result: $result');
}

int multiply(int a, int b) {
  return a * b;
}

Expected Output:

Result: 15

Explanation:

Functions allow you to encapsulate a block of code into a reusable unit.
In this example, we define a function named multiply that takes two parameters (a and b) and returns their product.

Example 8: Classes and Objects

void main() {
  Person person = Person('John', 25);
  person.displayInfo();
}

class Person {
  String name;
  int age;

  Person(this.name, this.age);

  void displayInfo() {
    print('Name: $name');
    print('Age: $age');
  }
}

Expected Output:

Name: John
Age: 25

Explanation:

Classes and objects are the building blocks of object-oriented programming.
In this example, we define a Person class with a constructor and a method to display the person's information.

Example 9: Exception Handling

void main() {
  try {
    int result = 5 ~/ 0;
    print('Result: $result');
  } catch (e) {
    print('Error: $e');
  }
}

Expected Output:

Error: IntegerDivisionByZeroException

Explanation:

Exception handling allows you to catch and handle runtime errors.
In this example, we use a try-catch block to catch the IntegerDivisionByZeroException that occurs when dividing by zero.

Example 10: Libraries and Imports

import 'dart:math';

void main() {
  double radius = 5;
  double area = calculateArea(radius);
  print('Area: $area');
}

double calculateArea(double radius) {
  return pi * pow(radius, 2);
}

Expected Output:

Area: 78.53981633974483

Explanation:

Dart provides a wide range of libraries that offer additional functionality.
In this example, we import the dart:math library to access the pi constant and the pow() function for calculating the area of a circle.

Congratulations! We have covered various fundamental concepts such as variables, data types, arithmetic operations, conditional statements, loops, lists, functions, classes, exception handling, and libraries.

Comparison with other languages

Dart shares similarities with several programming languages, but it also has some unique features that set it apart:

JavaScript: Dart was initially designed as an alternative to JavaScript, with the goal of providing better performance and tooling. Dart offers a more structured and typed approach compared to JavaScript, making it easier to catch errors early on.
Java and C++: Dart's syntax and object-oriented features resemble those of Java and C++. Developers familiar with these languages will find it relatively easy to transition to Dart.
Python: Dart shares similarities with Python in terms of code readability and simplicity. Both languages focus on clean and expressive code, making them beginner-friendly.
Flutter: Dart is the primary language used for developing applications with the Flutter framework. Flutter is a popular cross-platform framework for building mobile apps, and Dart's features are optimized for creating high-performance, visually-rich applications.

Conclusion

Dart is a powerful and versatile programming language that offers a combination of performance, ease of use, and flexibility. Its features such as strong typing, garbage collection, and asynchronous programming make it suitable for a wide range of applications. With its close integration with Flutter, Dart has become a popular choice for building cross-platform mobile apps. To learn more about Dart, visit the official Dart website at dart.dev.

I hope this tutorial helps you get started with Dart programming!

Introduction to Dart​

History​

Features​

Hello World in Dart​

Examples​

Example 1: Hello, World!​

Example 2: Variables and Data Types​

Example 3: Arithmetic Operations​

Example 4: Conditional Statements​

Example 5: Loops​

Example 6: Lists​

Example 7: Functions​

Example 8: Classes and Objects​

Example 9: Exception Handling​

Example 10: Libraries and Imports​

Comparison with other languages​

Conclusion​

Introduction to Dart

History

Features

Hello World in Dart

Examples

Example 1: Hello, World!

Example 2: Variables and Data Types

Example 3: Arithmetic Operations

Example 4: Conditional Statements

Example 5: Loops

Example 6: Lists

Example 7: Functions

Example 8: Classes and Objects

Example 9: Exception Handling

Example 10: Libraries and Imports

Comparison with other languages

Conclusion