Are there any common pitfalls when trying to replace characters in PHP strings?

One common pitfall when trying to replace characters in PHP strings is not using the correct syntax for the str_replace() function. Make sure to provide the correct parameters in the function call: the character to be replaced, the character to replace it with, and the string to search within. Additionally, be aware of case sensitivity when replacing characters.

// Example of replacing characters in a PHP string
$string = "Hello, world!";
$new_string = str_replace("o", "0", $string); // Replaces all occurrences of "o" with "0"
echo $new_string;