PHP if Operators - PHP Tutorial

In PHP, the if statement often relies on comparison operators and logical operators to evaluate conditions. These operators help determine whether certain conditions are true or false, enabling your code to execute specific actions accordingly.

Comparison Operators

Comparison operators are used within if statements to compare two values.

Example 1: Basic Comparison

Check whether $gear is equal to 6:

$gear = 6;

if ($gear == 6) {
    echo "You're riding at top gear!";
}

PHP
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$gear = 6;​if ($gear == 6) {    echo "You're riding at top gear!";}

To compare values effectively, you need to use one of PHP’s comparison operators, as detailed below:

Operator	Name	Result
`==`	Equal	Returns `true` if the two values are the same
`===`	Identical	Returns `true` if the two values and their data types are exactly the same
`!=`	Not Equal	Returns `true` if the two values are not the same
`<>`	Not Equal	Returns `true` if the two values are not the same (alternative to `!=`)
`!==`	Not Identical	Returns `true` if the values or their data types differ
`>`	Greater Than	Returns `true` if the first value is larger than the second
`<`	Less Than	Returns `true` if the first value is smaller than the second
`>=`	Greater or Equal	Returns `true` if the first value is greater than or equal to the second
`<=`	Less or Equal	Returns `true` if the first value is less than or equal to the second

Logical Operators

Logical operators allow you to evaluate multiple conditions within a single if statement.

Example 2: Combining Conditions

Check if $speed is greater than $minimum and less than $maximum:

$speed = 90;
$minimum = 60;
$maximum = 120;

if ($speed > $minimum && $speed < $maximum) {
    echo "You're driving at a safe speed.";
}

PHP
 
$speed = 90;$minimum = 60;$maximum = 120;​if ($speed > $minimum && $speed < $maximum) {    echo "You're driving at a safe speed.";}

PHP provides several logical operators for combining conditions:

Operator	Name	Description
`and`	And	Returns `true` if both conditions are true
`&&`	And	Returns `true` if both conditions are true
`or`	Or	Returns `true` if at least one condition is true
`\|\|`	Or	Returns `true` if at least one condition is true
`xor`	Xor	Returns `true` if only one condition is true (not both)
`!`	Not	Returns `true` if the condition is false

Checking Multiple Conditions

You can chain together multiple conditions using logical operators for more complex evaluations.

Example 3: Multiple Comparisons

Determine if $modelYear falls within a range:

$modelYear = 2021;

if ($modelYear == 2019 || $modelYear == 2020 || $modelYear == 2021 || $modelYear == 2022) {
    echo "This is a recent car model.";
}

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$modelYear = 2021;​if ($modelYear == 2019 || $modelYear == 2020 || $modelYear == 2021 || $modelYear == 2022) {    echo "This is a recent car model.";}

In this example, the || operator checks whether $modelYear matches any of the specified years.