PHP Conditions

Conditions allow programs to make decisions.

Without conditions, every program would execute exactly the same way every time.

Conditions are used everywhere:

• Login Systems
• Permissions
• APIs
• PocketMine Plugins
• Authentication
• Web Panels

---

Boolean Values

A condition always evaluates into:

true
false

---

if Statement

$age = 18;

if ($age >= 18) {
    echo "Adult";
}

Output:

Adult

---

if else

$online = false;

if ($online) {
    echo "Player Online";
} else {
    echo "Player Offline";
}

---

elseif

$rank = "vip";

if ($rank === "owner") {

    echo "Owner";

} elseif ($rank === "admin") {

    echo "Admin";

} elseif ($rank === "vip") {

    echo "VIP";

} else {

    echo "Player";

}

---

Comparison Operators

Operator	Meaning
==	Equal
===	Identical
!=	Not Equal
!==	Not Identical
>	Greater Than
<	Less Than
>=	Greater Than Equal
<=	Less Than Equal

---

Examples

Equal

$a = 5;
$b = 5;

if ($a == $b) {
    echo "Equal";
}

---

Identical

$a = 5;
$b = "5";

var_dump($a == $b);
var_dump($a === $b);

Output:

true
false

---

Greater Than

if ($money > 1000) {
    echo "Rich";
}

---

Less Than

if ($health < 10) {
    echo "Low Health";
}

---

Greater Than Equal

if ($level >= 50) {
    echo "Unlocked";
}

---

Less Than Equal

if ($health <= 0) {
    echo "Dead";
}

---

Logical Operators

Operator	Meaning
&&	AND
`
!	NOT

---

AND Operator

if (
    $isOnline &&
    $isAdmin
) {

    echo "Staff Member";

}

---

OR Operator

if (
    $rank === "owner" ||
    $rank === "admin"
) {

    echo "Staff";

}

---

NOT Operator

if (
    !$player->isBanned()
) {

    echo "Allowed";

}

---

Ternary Operator

$status =
$online
? "Online"
: "Offline";

---

Null Coalescing Operator

$name =
$_GET["name"] ?? "Guest";

---

Switch Statement

switch ($rank) {

    case "owner":
        echo "Owner";
        break;

    case "admin":
        echo "Admin";
        break;

    case "vip":
        echo "VIP";
        break;

    default:
        echo "Player";
}

---

Match Expression

PHP 8+

$prefix = match ($rank) {

    "owner" => "[Owner]",
    "admin" => "[Admin]",
    "vip" => "[VIP]",

    default => "[Player]"
};

---

PocketMine Example

if (
    $sender->hasPermission(
        "zyro.admin"
    )
) {

    $sender->sendMessage(
        "Access Granted"
    );

}

---

Login Example

if (
    $username === "admin" &&
    $password === "123"
) {

    echo "Login Success";

}

---

Common Mistakes

Wrong

if ($rank = "admin")

This assigns a value.

---

Correct

if ($rank === "admin")

---

Best Practices

✅ Prefer:

===
!==

instead of:

==
!=

---

✅ Use Match expressions in PHP 8+

---

✅ Avoid deeply nested conditions.

---

Exercises

1. Check if age is adult.
2. Create rank permission system.
3. Build login validator.
4. Convert switch to match.

---

Quiz

Which operator checks identical values?

===

---

Which operator means OR?

||

---

References

https://www.php.net/manual/en/control-structures.if.php

https://www.php.net/manual/en/control-structures.switch.php

https://www.php.net/manual/en/control-structures.match.php

---

Next Chapter

➡ PHP Loops