Heim > Artikel > Backend-Entwicklung > preg_replace – Wie analysiere ich versteckte Variablen in Variablen in PHP?
<code>$a = " #0 and #1 or (#0)"; $items = array( "a>1", "b>0" ); $str = preg_replace("/#(\w+)/","\$items[$1]",$a); echo $str;</code>
输出结果: $items[0] and $items[1] or ($items[0])
怎么才能让输出结果是:a>1 and b>0 or (a>1)?
请各位大神帮忙看一下,谢谢!
<code>$a = " #0 and #1 or (#0)"; $items = array( "a>1", "b>0" ); $str = preg_replace("/#(\w+)/","\$items[$1]",$a); echo $str;</code>
输出结果: $items[0] and $items[1] or ($items[0])
怎么才能让输出结果是:a>1 and b>0 or (a>1)?
请各位大神帮忙看一下,谢谢!
正则
<code>$items = [ 'a > 1', 'b > 0', 'abc' => 'c > 1' ]; $subject = '#0 and #1 or (#0) and #abc #nooo'; echo preg_replace_callback('/#([a-z0-9_]+)/i', function($v) use ($items){ return isset($items[$v[1]]) ? $items[$v[1]] : $v[0]; }, $subject);</code>
<code>a > 1 and b > 0 or (a > 1) and c > 1 #nooo</code>