Loops in PHP - Formula Sheet

PHP Loop Syntax Structures

1. The For Loop

Syntax:

for (initialization; condition; increment/decrement) { // statements }

Parameters:

• initialization: Runs once at loop start to define the loop counter's initial state.
• condition: Checked before each loop pass. The loop body executes if true and terminates if false.
• increment/decrement: Evaluated at the end of each iteration to update the loop counter.

2. The While Loop

Syntax:

while (condition) { // statements }

Parameters:

• condition: Evaluated before every iteration. The loop body executes as long as this logical test is true.

3. The Do...While Loop

Syntax:

do { // statements } while (condition);

Parameters:

• condition: Tested at the end of each loop pass. The code block is guaranteed to run at least once. Note the required trailing semicolon.

4. The Foreach Loop

Syntax (Value Traversal):

foreach (\(array_variable as \)value) { // statements }

Syntax (Key-Value Traversal):

foreach (\(array_variable as \)key => \(value) { // statements }

Parameters:

• \)array_variable: The target array to traverse.
• \(key: Temporarily holds the key of the current element on each iteration.
• \)value: Temporarily holds the value of the current element on each iteration.