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Detailed explanation of str_replace() substring replacement function
Detailed explanation of str_replace() substring replacement function
In the last article, we introduced "Converting php variables to json format data". In this article, we will introduce strings. String is a common data type that is operated during php. For substring operations, php has built-in str_replace(). This article will show you Let’s take a look. First, let's take a look at the syntax of the str_replace() function.
str_replace ( mixed $search , mixed $replace , mixed $subject , int &$count = ? )
$search: The target that needs to be searched
$replace: The value that needs to be replaced with the target
$subject: String or array to be processed
$count: Optional, the number of times replacement occurs
-
Return value: This function returns the replaced array or string.
Code example:
1. The parameters are all strings
<?php
$str="Chinese php.com is better";
$str2 = str_replace("com", "cn",$str,$count);
echo $str.",经过".$count."次替换后,变为:".$str2;
?>输出:Chinese php.com is better,经过1次替换后,变为:Chinese php.cn is better
2. The parameters are all arrays
<?php $search = array('A', 'B', 'C', 'D', 'E'); $replace = array('B', 'C', 'D', 'E', 'F'); $subject = 'A'; echo str_replace($search, $replace, $subject);
输出:F
Recommendation: 《2021 Summary of PHP interview questions (Collection)》《php video tutorial》
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