control_structures.md

🎛️ Control Structures in PHP

Take charge of your code - Control Structures direct the flow of execution in PHP!

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🌟 What Are Control Structures?

Control structures let you dictate how and when code runs. They include conditionals (e.g., if) for decisions and loops (e.g., for) for repetition—essential for dynamic programs!

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🛠️ Types of Control Structures

Let’s dive into PHP’s key control structures with examples!

1. Conditional Statements

Make decisions based on conditions.

if, else if, else

Execute code if a condition is true.

$age = 20;
if ($age >= 18) {
    echo "You’re an adult!";
} else if ($age >= 13) {
    echo "You’re a teen!";
} else {
    echo "You’re a kid!";
}
// Outputs: You’re an adult!

switch

Handle multiple cases efficiently.

$day = 3;
switch ($day) {
    case 1:
        echo "Monday";
        break;
    case 2:
        echo "Tuesday";
        break;
    case 3:
        echo "Wednesday";
        break;
    default:
        echo "Unknown day";
}
// Outputs: Wednesday

Feature	if	switch
Use Case	Flexible conditions	Multiple fixed values
Syntax	More verbose	Cleaner for cases
Break Needed	No	Yes (or fall-through)

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2. Looping Structures

Repeat code as needed.

for

Run a block a specific number of times.

for ($i = 1; $i <= 5; $i++) {
    echo "Count: $i<br>";
}
// Outputs:
// Count: 1
// Count: 2
// Count: 3
// Count: 4
// Count: 5

while

Loop while a condition is true.

$count = 0;
while ($count < 3) {
    echo "Tick: $count<br>";
    $count++;
}
// Outputs:
// Tick: 0
// Tick: 1
// Tick: 2

do-while

Loop at least once, then check the condition.

$num = 5;
do {
    echo "Number: $num<br>";
    $num--;
} while ($num > 0);
// Outputs:
// Number: 5
// Number: 4
// Number: 3
// Number: 2
// Number: 1

foreach

Iterate over arrays or objects.

$colors = ["red", "blue", "green"];
foreach ($colors as $color) {
    echo "Color: $color<br>";
}
// Outputs:
// Color: red
// Color: blue
// Color: green

Loop Type	Best For	Condition Checked
for	Known iterations	Before each
while	Unknown iterations	Before each
do-while	At least one run	After each
foreach	Arrays/iterables	N/A

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3. Control Flow Modifiers

Alter loop or conditional behavior.

break

Exit a loop or switch early.

for ($i = 0; $i < 10; $i++) {
    if ($i == 4) {
        break;
    }
    echo "$i ";
}
// Outputs: 0 1 2 3

continue

Skip to the next loop iteration.

for ($i = 0; $i < 5; $i++) {
    if ($i == 2) {
        continue;
    }
    echo "$i ";
}
// Outputs: 0 1 3 4

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🔥 Combining Operators with Control Structures

Use operators (e.g., &&, >) to craft powerful logic.

$score = 85;
if ($score >= 90) {
    echo "Grade: A";
} elseif ($score >= 80 && $score < 90) {
    echo "Grade: B";
} else {
    echo "Grade: C";
}
// Outputs: Grade: B

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🎯 Best Practices

• Readability: Use braces {} even for single-line blocks.
• Nesting: Avoid deep nesting—keep it simple.
• Comments: Explain complex logic with // or /* */.

$items = ["apple", "banana", "orange"];
foreach ($items as $index => $item) {
    // Skip banana
    if ($item === "banana") {
        continue;
    }
    echo "$index: $item<br>";
}
// Outputs:
// 0: apple
// 2: orange

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➡️ Next: Functions

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