How to use regular expressions in php to match a certain character and delete it

Two methods: 1. Use preg_replace() to replace the matching characters with empty characters, the syntax is "preg_replace('/specified character/i','',$str)". 2. Use preg_filter(), the syntax is "preg_filter('/character/i','',$str)".

The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer

php uses regular matching Two methods to delete a certain character

Method 1: Use preg_replace() for regular replacement

preg_replace() function can perform regular replacement Expression search and replacement

You only need to use preg_replace() to perform a regular expression search for the specified character and replace it with a null character.

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);   
$str = &#39;1132hell0 2313&#39;;
$pattern = &#39;/l/i&#39;;
$replacement = &#39;&#39;;
echo preg_replace($pattern, $replacement, $str);
?>

Method 2: Use preg_filter() for regular replacement

preg_filter() is the same as preg_replace() and can be executed Regular expression search and replace.

Just execute a regular expression to search for the specified characters and replace them with null characters.

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);   
$str = &#39;1132hell0 2313&#39;;
echo "原字符串：".$str."<br>";
$pattern = &#39;/3/i&#39;;
$replacement = &#39;&#39;;
echo "处理后：".preg_filter($pattern, $replacement, $str);
?>

Explanation: The difference between preg_replace() and preg_filter()

preg_filter() function only returns the result of successful matching. And preg_replace() returns all results, regardless of whether the match is successful.

Recommended learning: "PHP Video Tutorial"

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