Concatenation of two strings in PHP program

In PHP, string concatenation is performed using the dot operator (.). This operator joins two or more strings together to create a single string.

Syntax

$result = $string1 . $string2;

Example 1: Concatenating Simple Strings

Let's start with a basic example of concatenating two string variables ?

<?php
    $val1 = 'Jack';
    $val2 = 'Sparrow';
    echo "First Name = $val1<br>";
    echo "Second Name = $val2<br>";
    $res = $val1 . $val2;
    echo "Concatenation = $res<br>";
?>

This will produce the following output ?

First Name = Jack
Second Name = Sparrow
Concatenation = JackSparrow

Example 2: Adding Spaces Between Strings

You can also concatenate strings with spaces or other characters in between ?

<?php
    $firstName = 'John';
    $lastName = 'Doe';
    $fullName = $firstName . ' ' . $lastName;
    echo "Full Name: $fullName<br>";
    
    // Using multiple concatenations
    $greeting = 'Hello, ' . $firstName . ' ' . $lastName . '!';
    echo $greeting;
?>

This will produce the following output ?

Full Name: John Doe
Hello, John Doe!

Example 3: Concatenating Numbers and Strings

PHP automatically converts numbers to strings during concatenation ?

<?php
    $a = 1.967;
    $b = 1.969;
    $res = $a . " and " . $b;
    echo "$res<br>";
    
    if((round($a, 2)) == (round($b, 2))) {
        echo "Both the values are equal when rounded!";
    } else {
        echo "Both the values aren't equal";
    }
?>

This will produce the following output ?

1.967 and 1.969
Both the values are equal when rounded!

Concatenation Assignment Operator

PHP also provides the .= operator for appending strings to existing variables ?

<?php
    $message = "Hello";
    $message .= " World";
    $message .= "!";
    echo $message;
?>

This will produce the following output ?

Hello World!

Conclusion

PHP string concatenation using the dot operator (.) is simple and flexible. Use . to join strings and .= to append to existing variables. PHP automatically handles type conversion during concatenation.