Use stripos() in php to get the first occurrence of a string

In the previous article, we introduced "Detailed explanation of str_replace() substring replacement function ". In this article we mainly introduce the stripos() function. Strings are a frequently used data type in PHP. In some special scenarios, we may need to get the position where a specified string first appears in a string. PHP has a built-in stripos() function. This article will take you through it. one look. The first thing I need to understand is the syntax of the function.
stripos ( string $haystack , string $needle , int $offset = 0 )
$haystack: The string to be found
$needle: The target character to be found
$offset: Optional, search starts from the specified character position. If it is a negative number, the search starts this number of characters from the end of the character.
Return value: The position where $needle appears in $haystack
Code example:
1. There are only two parameters: the string to be searched and the target character to be searched for
<?php $str="Chinese php.com is better"; echo "出现的位置:".(stripos($str,'com'))."<br>"; ?>
输出:出现的位置:12
2.Three parameters
<?php $str="Chinese php.com is better .com"; echo "第一次出现的位置:".(stripos($str,'com'))."<br>"; echo "第二次出现的位置:".(stripos($str,'com',(stripos($str,'com'))+1))."<br>"; ?>
输出:  第一次出现的位置:12
        第二次出现的位置:27Recommended: 《2021 PHP Interview Questions Summary (Collection)》《 php video tutorial》
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