Detailed Guide to PHP String Concatenation: Easily Combine Strings

Two Methods to Concatenate Strings in PHP

In PHP, string concatenation refers to joining two or more strings into one. There are mainly two ways to achieve this:

Dot Operator (.)

The dot operator (.) is the basic operator used to concatenate strings in PHP. It directly joins two strings to form a new string.

Example code:

$str1 = "Hello";
$str2 = "World";
$result = $str1 . $str2;  // Result is "HelloWorld"

Concatenation Assignment Operator (.=)

The concatenation assignment operator (.=) appends a string to the end of an existing string. It is equivalent to adding the right-hand string to the left-hand string.

Example code:

$str1 = "Hello";
$str1 .= "World";  // Equivalent to $str1 = $str1 . "World"

Usage Notes

• Both the dot operator and concatenation assignment operator achieve the same concatenation result.
• The concatenation operator has higher precedence than the assignment operator, so be mindful of execution order when using the concatenation assignment operator.
• PHP strings are immutable, meaning each concatenation creates a new string copy; frequent concatenation may impact performance.

Summary

Mastering these two string concatenation methods will help you handle PHP string operations more efficiently, whether it's simple joining or dynamic string building.