Dart is a statically typed language with a rich set of built-in data types. Understanding these types is crucial for efficient programming and type safety.

Basic Data Types

Numbers

Dart provides two number types:

int: For whole numbers
double: For floating-point numbers

Example:


int age = 30;
double price = 19.99;

Strings

Text is represented using the String type. Dart supports both single and double quotes for string literals.

Example:


String name = 'John Doe';
String message = "Hello, World!";

Booleans

The bool type represents true or false values.

Example:


bool isActive = true;
bool hasPermission = false;

Collection Types

Lists

Dart uses List for ordered collections of objects. Lists are similar to arrays in other languages.

Example:


List<String> fruits = ['apple', 'banana', 'orange'];

Sets

A Set is an unordered collection of unique items.

Example:


Set<int> numbers = {1, 2, 3, 4, 5};

Maps

Dart's Map type represents key-value pairs.

Example:


Map<String, int> ages = {
  'John': 30,
  'Jane': 25,
  'Bob': 40
};

Special Types

Dynamic

The dynamic type allows variables to hold values of any type.

Null Safety

Dart supports Null Safety, which helps prevent null reference errors. Use the ? operator to declare nullable types.

Example:


String? nullableName;
int nonNullableAge = 25;

Best Practices

Use specific types when possible for better type safety and code clarity.
Leverage Dart's type inference to reduce verbosity while maintaining type safety.
Consider using Dart Generics for more flexible and reusable code.
Be mindful of Type Promotion when working with nullable types.

Conclusion

Understanding Dart's data types is fundamental to writing efficient and error-free code. As you progress, explore more advanced topics like Dart Classes and Dart Interfaces to fully leverage Dart's type system.