PHP how to make case-insensitive version of str_replace

php editor Zimo will share with you how to use the str_ireplace function in PHP to achieve case-insensitive replacement. The str_ireplace function is a case-insensitive version of str_replace, which can help us replace strings more conveniently and improve development efficiency. Let’s learn how to correctly use the str_ireplace function to achieve case-insensitive replacement of strings!

Str_ireplace() function in PHP: case-insensitive str_replace()

Overview:

str_ireplace() function is a case-insensitive version of the str_replace() function in php. It performs a string search and replace operation, but ignores case.

grammar:

string str_ireplace(string $search, string $replace, string $subject[, int $count])

parameter:

• $search: The string to search for.
• $replace: The string to replace the search string.
• $subject: The string to search and replace for strings.
• $count: (optional) Maximum number of occurrences to replace (default: -1, means replace all occurrences).

usage:

The str_ireplace() function works similarly to the str_replace() function, except that it is not case-sensitive. This means that it can find and replace any occurrence of the search string within the string, regardless of the case of the match.

The following is an example of how to use the str_ireplace() function in a case-insensitive search:

$original_string = "This is a TEST string.";
$new_string = str_ireplace("test", "EXAM", $original_string);
echo $new_string; // Output: This is an EXAM string.

In this example, the str_ireplace() function searches $original_string for the "test" string (case-insensitive) and replaces it with the "EXAM" string. The result is stored in $new_string.

and str_replace():

The main difference between the str_ireplace() function and the str_replace() function is case sensitivity. The str_replace() function is case-sensitive, while the str_ireplace() function is not case-sensitive. This means that the str_ireplace() function can find and replace case-insensitive matches in a string.

Efficiency considerations:

Be aware of the efficiency of the str_ireplace() function when using it on large strings. Because it performs a case-insensitive search, it is slower than the str_replace() function. If you don't care about case sensitivity, you should use the str_replace() function for better performance.

Other matters worth noting:

• str_ireplace() function works correctly with UTF-8 strings.
• If you also want to search and replace newlines, you can use str_ireplace(" ", "
  ", $string) to implement.
• str_ireplace() function enables advanced search and replacement using PCRE mode.

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