Master PHP’s strtr(): Simple, Multi‑Replace, and Partial String Substitutions

In PHP programming, the strtr() function is a useful string replacement function that replaces specified characters or substrings with others. This article introduces its usage and provides concrete code examples.

The basic syntax is: strtr(string $str, array $replace) Here $str is the original string, and $replace is an array of characters or strings to replace. The $replace parameter can be an associative or indexed array where each key/value pair represents the target and replacement.

Common use cases:

1. Simple character replacement

$text = "Hello World";
echo strtr($text, "World", "PHP"); // output: Hello PHP

This replaces "World" with "PHP".

2. Replace multiple characters

$text = "I like apples and oranges.";
$replace = array("apples" => "bananas", "oranges" => "grapes");
echo strtr($text, $replace); // output: I like bananas and grapes.

Here $replace is an associative array mapping strings to their replacements.

3. Replace character sequences

$text = "I love PHP programming.";
$replace = array("PHP" => "Java", "programming" => "coding");
echo strtr($text, $replace); // output: I love Java coding.

This swaps "PHP" with "Java" and "programming" with "coding".

4. Partial character replacement

$text = "I am a programmer.";
$replace = array("a" => "", "r" => "");
echo strtr($text, $replace); // output: I m pogamm.

In this example, specific characters are removed by mapping them to empty strings.

Summary

The strtr() function is a powerful tool for string replacement in PHP. It can handle simple character swaps, multiple replacements, sequence substitutions, and partial replacements, making string manipulation more convenient and flexible.