201 lines
3.4 KiB
PHP
201 lines
3.4 KiB
PHP
<?php
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// -----------------------------
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// IF statement
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// -----------------------------
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if ($condition) {
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// code.
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}
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// E.g.
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if ($year === 2024) {
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$isOlympicYear = TRUE;
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}
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// Bonus: IF statements with a lot of conditions
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if (
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$condition_1 &&
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(
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$condition_2 ||
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$condition_3
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) &&
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$condition_4
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) {
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// code.
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}
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// -----------------------------
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// IF/ELSE statement
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// -----------------------------
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if ($condition) {
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// code.
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}
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else {
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// other code.
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}
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// E.g.
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if ($year === 2024) {
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$isOlympicYear = TRUE;
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}
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else {
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$isOlympicYear = FALSE;
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}
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// Alternatively, you could write the above like this.
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$isOlympicYear = FALSE;
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if ($year === 2024) {
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$isOlympicYear = TRUE;
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}
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// -----------------------------
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// ELSEIF statements.
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// -----------------------------
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if ($condition_1) {
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// code.
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}
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elseif ($condition_2) {
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// other code.
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}
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else {
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// other other code.
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}
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// E.g.
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if ($year === 2024) {
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$isOlympicYear = TRUE;
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}
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elseif ($year === 2025) {
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$isOlympicYear = FALSE;
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}
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// -----------------------------
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// Nesting statements
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// -----------------------------
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// E.g.
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if ($year === 2024) {
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$isOlympicYear = TRUE;
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if ($city === 'Paris') {
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echo "Bonjour!";
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}
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else {
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echo "Hello!";
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}
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}
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// -----------------------------
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// Early Return statements
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// -----------------------------
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function checkAge($age) {
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// Early return if age is less than 18
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if ($age < 18) {
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return "Too young";
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}
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// Continue with the function if age is 18+
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return "Welcome!";
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}
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echo checkAge(16); // Outputs: Too young
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echo checkAge(20); // Outputs: Welcome!
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// -----------------------------
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// Ternary Expressions
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// - Only good for replacing non-complex IF/ELSE statements
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// -----------------------------
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$age = 20;
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$can_vote = ($age >= 18) ? 'Yes' : 'No'
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// Alternatively, you could write the above like this, but the above saves lines of code.
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if ($age >= 18) {
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$can_vote = 'Yes';
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}
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else {
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$can_vote = 'No';
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}
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// -----------------------------
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// Switch statements
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// -----------------------------
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// E.g.
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switch ($isOlympicYear) {
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case 2023:
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break; // Without a break, the code will continue executing to the next case.
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case 2024:
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break;
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case 2025:
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break;
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default: // Default is the equivalent to an ELSE
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break;
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}
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// Using a switch like above instead of the following
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if ($year === 2023) {
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//
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}
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elseif ($year === 2024) {
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//
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}
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elseif ($year === 2025) {
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//
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}
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// -----------------------------
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// For loops
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// -----------------------------
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// E.g.
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for ($i = 1; $i < 5; $i++) {
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echo "This is the $i -th iteration.";
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}
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// -----------------------------
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// While loops
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// -----------------------------
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// E.g.
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$i = 1;
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while ($i < 5) {
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echo "This is the $i -th iteration.";
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$i++;
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}
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// -----------------------------
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// Passing Arguments by Reference
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// -----------------------------
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function add_five(&$value) {
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$value += 5;
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}
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$num = 2;
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add_five($num);
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echo $num; // Outputs: 7
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// -----------------------------
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// Using the ... operator
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// - Allows for any number of arguments
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// -----------------------------
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function sum(...$numbers) {
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$sum = 0;
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for ($i = 0; $i < count($numbers); $i++) {
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$sum += $numbers[$i];
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}
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return $sum;
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}
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echo sum(1, 2, 3, 4); // Output: 10
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