PHP str_replace() Function

The str_replace() function replaces some characters with some other characters in a string.
This function works by the following rules:

• If the string to be searched is an array, it returns an array
• If the string to be searched is an array, find and replace is performed with every array element
• If both find and replace are arrays, and replace has fewer elements than find, an empty string will be used as replace
• If find is an array and replace is a string, the replace string will be used for every find value

Note: This function is case-sensitive. Use the str_ireplace() function to perform a case-insensitive search.

Note: This function is binary-safe.

Syntax : str_replace(find,replace,string,count)

 <?php
echo str_replace("world","Peter","Hello world!");
?>