In PHP, comparison operators allow developers to compare values and evaluate logical conditions within their code. These operators enable the comparison of variables, constants, and expressions to determine their equality, inequality, or relative order.
Let’s delve into PHP’s comparison operators and understand how they work.
== (Equals):
The equals operator, denoted by ‘==’, compares two values and returns true if they are equal. For example, $a == $b evaluates to true if $a is equal to $b in terms of their values. It performs type coercion, allowing for comparisons between different data types.
=== (Identical):
The identical operator, represented by ‘===’, compares both the values and the data types of two expressions. It returns true if both the values and data types are identical. For instance, $a === $b evaluates to true only if $a and $b have the same value and data type.
!= (Not Equal):
The not equal operator, denoted by ‘!=’, checks if two values are not equal. It returns true if the values are different. For example, $a != $b evaluates to true if $a is not equal to $b.
!== (Not Identical):
The not identical operator, represented by ‘!==’, compares both the values and the data types of two expressions. It returns true if either the values or the data types (or both) are not identical. For instance, $a !== $b evaluates to true if $a and $b have different values or different data types.
<> (Not Equal – Alternative):
The not equal operator (alternative syntax), denoted by ‘<>’, is an alternative to ‘!=’. It functions similarly, checking if two values are not equal. For example, $a <> $b evaluates to true if $a is not equal to $b.
< (Less Than):
The less than operator, represented by ‘<‘, checks if the value on the left is less than the value on the right. It returns true if the left operand is smaller than the right operand. For instance, $a < $b evaluates to true if $a is less than $b.
> (Greater Than):
The greater than operator, denoted by ‘>’, checks if the value on the left is greater than the value on the right. It returns true if the left operand is larger than the right operand. For example, $a > $b evaluates to true if $a is greater than $b.
<= (Less Than or Equal To):
The less than or equal to operator, represented by ‘<=’, checks if the value on the left is less than or equal to the value on the right. It returns true if the left operand is smaller than or equal to the right operand. For instance, $a <= $b evaluates to true if $a is less than or equal to $b.
>= (Greater Than or Equal To):
The greater than or equal to operator, denoted by ‘>=’, checks if the value on the left is greater than or equal to the value on the right. It returns true if the left operand is larger than or equal to the right operand. For example, $a >= $b evaluates to true if $a is greater than or equal to $b.
By utilizing these comparison operators, developers can make logical evaluations and implement conditional statements to control the flow of their PHP programs. These operators are essential for tasks such as validating user input, sorting data, and implementing decision-making processes.
It’s important to note that comparison operators return boolean values (true or false) based on the evaluation of the conditions. Additionally, when comparing values of different types, PHP performs type coercion to facilitate the comparison, which can have implications when working with different data types
