Windows API Reference - Fundamentals
Introduction
This section introduces the fundamental concepts of the Windows API.
Key Concepts
- API (Application Programming Interface): A set of rules and specifications that allow software components to communicate with each other.
- Functions: Code blocks that perform specific tasks.
- Data Types: The kind of data that the API handles (e.g., integers, strings, booleans).
- Parameters: Input values passed to functions.
- Return Values: The result of a function call.
Data Types
Common Data Types in Windows:
- Integer: Whole numbers (e.g., 10, -5, 0).
- String: Text data (e.g., "Hello, world!").
- Boolean: True or False.
- Double: Numeric values with decimal points (e.g., 3.14, -2.5).
- Char: Single characters.
Functions
Functions are reusable blocks of code. They accept input (parameters), perform some action, and return a result.
Example: `GetSystemMetrics()` returns the width and height of the screen.
Parameters
Parameters are inputs to a function. They're required and defined within the function definition.
Example: `Print("Hello")` takes a string argument.
Return Values
The return value of a function is the result it produces.
Example: `CalculateArea()` returns the area of a rectangle.