How does php realize the swapping of substring positions? This article mainly introduces the method of swapping and exchanging substring positions in PHP. It can realize the function of exchanging two substrings in a simple string. It involves PHP string operations, insertion, replacement and other related skills. Friends who need it You can refer to it. I hope to be helpful.
The details are as follows:
<?php /*子字符串位置互换 */ $str1="Tom"; $str2="Jack"; $str="This is an example,you see Tom tell Jack something"; function str_change($str,$str1,$str2){ $len1=strlen($str1); $len2=strlen($str2); $pos1=strpos($str,$str1); $str=substr_replace($str,$str2,$pos1,$len1);//替换$str1为$str2 $pos2= strpos($str,$str2,$len1+$pos1);//定位替换后字符串中原$str2字段的位置 return substr_replace($str,$str1,$pos2,$len2);//替换$str2为$str1 } echo str_change($str,$str1,$str2); ?>
The running result is:
This is an example, you see Jack tell Tom something
Related recommendations:
php Related functions for string escaping
php String splitting Introduction to and comparison
php Detailed explanation of the use of string regular replacement function preg_replace
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