Class declaration syntax in PHP - Step-by-Step Execution

Concept Flow - Class declaration syntax

Start

↓

Write 'class' keyword

↓

Name the class

↓

Open curly brace '{'

↓

Declare properties and methods

↓

Close curly brace '}'

↓

Class ready to use

↓

End

This flow shows the steps to declare a class in PHP: start with the keyword, name it, add braces, then add properties and methods inside.

Execution Sample

PHP

<?php
class Car {
  public $color;
  public function drive() {
    echo "Driving";
  }
}

This code declares a class named Car with a property color and a method drive that prints 'Driving'.

Execution Table

Step	Action	Code Part	Result
1	Start class declaration	class Car {	Class named Car begins
2	Declare property	public $color;	Property $color added
3	Declare method	public function drive() {	Method drive starts
4	Method body	echo "Driving";	Output command inside method
5	Close method	}	Method drive ends
6	Close class	}	Class Car declaration ends
7	Class ready	N/A	Class Car can be used now

💡 Class declaration ends after closing brace '}', ready for use.

Variable Tracker

Variable	Start	After Step 2	After Step 6
$color	undefined	declared as public property	property ready in class

Key Moments - 2 Insights

Why do we use curly braces {} after the class name?

Curly braces define the start and end of the class body where properties and methods are declared, as shown in steps 1 and 6 of the execution_table.

What does 'public' mean before a property or method?

'Public' means the property or method can be accessed from outside the class. This is shown in step 2 and 3 where $color and drive() are declared public.

Visual Quiz - 3 Questions

Look at the execution_table, what happens at step 4?

A The class declaration ends

B The method drive() starts

C The method drive() outputs 'Driving'

D A property is declared

💡 Hint

Check the 'Action' and 'Result' columns at step 4 in the execution_table.

At which step is the class Car fully declared and ready to use?

A Step 7

B Step 3

C Step 6

D Step 2

💡 Hint

Look for the step where the class is marked 'ready for use' in the execution_table.

If we remove the closing brace '}' at step 6, what happens?

A The property $color is removed

B The class declaration is incomplete and causes an error

C The class still works fine

D The method drive() is deleted

💡 Hint

Refer to the exit_note and the importance of closing braces in the execution_table.

Concept Snapshot

PHP Class Declaration Syntax:
- Use 'class ClassName { }' to declare a class.
- Inside braces, declare properties and methods.
- Use 'public' to allow outside access.
- Curly braces define class body.
- Class ready after closing brace.

Full Transcript

This visual execution shows how to declare a class in PHP. First, write the keyword 'class' followed by the class name. Then open curly braces to start the class body. Inside, declare properties like public $color and methods like public function drive(). The method can have code like echo 'Driving'. Close the method and then close the class with a curly brace. The class is then ready to use. Curly braces are important to mark the class body. The 'public' keyword means the property or method can be accessed from outside the class. Missing the closing brace causes errors. This step-by-step helps beginners see how PHP class declaration works.