What are common mistakes to avoid when using if statements in PHP?

One common mistake to avoid when using if statements in PHP is forgetting to use double equals (==) for comparison instead of a single equals sign (=), which is used for assignment. This can lead to unintended results or errors in your code. Another mistake is not using proper logical operators like && (and) or || (or) when combining multiple conditions in an if statement. Make sure to also handle all possible scenarios, including edge cases, to ensure your if statements are robust and accurate.

// Incorrect comparison using assignment operator
$number = 5;
if($number = 5){
    echo "Number is 5";
}

// Correct comparison using double equals
$number = 5;
if($number == 5){
    echo "Number is 5";
}

// Incorrect logical operator
$age = 25;
if($age > 18 && $age < 30){
    echo "Age is between 18 and 30";
}

// Correct logical operator
$age = 25;
if($age > 18 && $age < 30){
    echo "Age is between 18 and 30";
}