一个字符串难题~
<?php<br /> $a="<fieldset>1<fieldset>2<fieldset>3<fieldset>4</fieldset></fieldset></fieldset></fieldset>";<br /> echo $a;<br /> ?>
$a="<fieldset>1<fieldset>2<fieldset>4</fieldset></fieldset></fieldset>";
<br />
$a="<fieldset>1<fieldset>2<fieldset>3<fieldset>4</fieldset></fieldset></fieldset></fieldset>";<br />
$aa=preg_replace("/((<fieldset>[^<]+){2})(<fieldset>[^<]+((<fieldset>[^<]+<\/fieldset>)*)<\/fieldset>)((<\/fieldset>){2})/isU", "\\1\\4\\6", $a);<br />
echo $aa;<br />
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