php reverse string method

During the interview for PHP-related jobs, we are likely to encounter this problem, how to reverse a string. Below we will answer this question for you.

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##Method 1

Use the strrev() function to reverse a string.

Grammar strrev(string)

Example

<?php 
echo strrev("Hello World!"); 
?>

Output: !dlroW olleH

Method 2

Split the string into an array, and then traverse and splice it, as follows

function revstr($str)
{
	if (strlen($str) <= 1) return $str;
 
	$newstr  = &#39;&#39;;
	$str2arr = str_split($str,1);
	foreach ($str2arr as $word) {
		$newstr = $word.$newstr;
	}
 
	return $newstr;
}

Method 3## Use recursion, the code is as follows

function revstr($str)
{
	if (strlen($str) <= 1) return $str;
 
	$newstr = &#39;&#39;;
	$newstr .= substr($str,-1).revstr(substr($str,0,strlen($str)-1));
 
	return $newstr;
}

ps: This method should be what the interviewer wants to see Answer.

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