What are some potential pitfalls to be aware of when using str_replace in PHP?

One potential pitfall when using str_replace in PHP is that it is case-sensitive by default. This means that if you are trying to replace a string but the case does not match exactly, the replacement will not occur. To solve this issue, you can use the function str_ireplace instead, which is case-insensitive.

// Using str_ireplace to perform a case-insensitive replacement
$string = "Hello World";
$new_string = str_ireplace("hello", "hi", $string);
echo $new_string; // Output: "hi World"