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How to write reverse output in php: 1. Create a PHP sample file; 2. Pass "for ($i=1; $i<=strlen($str); $i ){echo substr($ str , -$i , 1)}" method to reverse the string.
The operating environment of this article: Windows 7 system, PHP version 7.1, DELL G3 computer
How to write the reverse output method in php?
1. If it is a string or an array directly, you can use strrev or array_reverse to reverse it respectively.
2. Write an algorithm yourself to reverse the string.
$str = "abcdef"; for ( $i=1; $i<=strlen($str); $i++) { echo substr($str , -$i , 1) }
php positive sequence output sample code
Implementation code:
// 正序 foreach($files as $file_num => $file) { if(is_file($directory.$file)){ //$file = iconv("gb2312","UTF-8",$file); //或者 iconv("gb2312","UTF-8",$value); $date = substr($file,0,9); echo '<li class="world-cup-'.$date.'">'; echo '<a href="'.$directory.$file.'" rel="worldcup" title="巴西世界杯赛事'.$date.'">'; echo '<img src="'.$directory.$file.'" alt="">'; echo '</a>'; echo '</li>'; } }
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