String Operators
Part of the Fundamentals section of Coddy's PHP journey — lesson 22 of 71.
Just like numbers have arithmetic operators, strings have their own operators for combining text. You've already seen the concatenation operator (.) in an earlier lesson. Now let's look at its combined assignment counterpart.
The concatenation assignment operator (.=) appends text to an existing string variable, following the same pattern as += for numbers:
<?php
$message = "Hello";
$message = $message . " World"; // The long way
$message .= "!"; // The shorthand way
echo $message; // Outputs: Hello World!
?>This operator is particularly useful when building strings piece by piece:
<?php
$greeting = "Welcome";
$greeting .= ", ";
$greeting .= "John";
$greeting .= "!";
echo $greeting; // Outputs: Welcome, John!
?>Remember: use . to join strings together, and .= to append to an existing string variable. These are the two string operators you'll use most often in PHP.
Challenge
EasyRead three strings from input: a greeting, a name, and a punctuation mark.
Create a variable called $message and initialize it with the greeting. Then use the concatenation assignment operator (.=) to:
- Append a space and the name to
$message - Append the punctuation mark to
$message
Print the final message.
Example:
If the inputs are Hello, Alice, and !, the output should be:
Hello Alice!Cheat sheet
The concatenation assignment operator (.=) appends text to an existing string variable:
<?php
$message = "Hello";
$message .= " World"; // Appends " World" to $message
$message .= "!"; // Appends "!" to $message
echo $message; // Outputs: Hello World!
?>This is shorthand for $message = $message . " World";
Building strings piece by piece:
<?php
$greeting = "Welcome";
$greeting .= ", ";
$greeting .= "John";
$greeting .= "!";
echo $greeting; // Outputs: Welcome, John!
?>Try it yourself
<?php
// Read input
$greeting = trim(fgets(STDIN));
$name = trim(fgets(STDIN));
$punctuation = trim(fgets(STDIN));
// TODO: Write your code below
// Initialize $message with the greeting
// Use .= to append a space and the name
// Use .= to append the punctuation mark
// Output the result
echo $message;
?>
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Fundamentals
4Comparison & Logical Operators
Comparison OperatorsEquality & IdentityLogical Operators Part 1Logical Operators Part 2Recap - Simple Logic2Variables and Data Types
NumbersStrings and QuotesBooleansNaming ConventionsRecap - Variable InitEmpty VariablesString ConcatenationGetting User InputCast to Different Types5Conditional Logic
If StatementIf - ElseThe Ternary OperatorNull Coalescing OperatorSwitch StatementRecap - Making Decisions3Basic Operators
Arithmetic OperatorsModulo OperatorExponentiation OperatorCombined AssignmentIncrement/DecrementOperator PrecedenceRecap - Simple CalculationsString Operators