关于截取以逗号隔开的字符串位数解决办法

$s = '0,48423,48425,48427,48419,48413,48415,48417,48418,48414,48416,48411,';<br />
<br />
echo preg_replace('/\d+,((?:\d+,){3}\d+).*/', '$1', $s);<br />

$string = "0,48423,48425,48427,48419,48413,48415,48417,48418,48414,48416,48411,";<br />
 $ar=explode(',',$string);<br />
  $arr=array_slice($ar,1,4);<br />
  echo join(',',$arr);

<br />
	$str="0,48423,48425,48427,48419,48413,48415,48417,48418,48414,48416,48411,";<br />
	function jiequ($str,$a,$b){<br />
		$ar=explode(",",$str);<br />
		for($i=$a;$i<$b;$i++){<br />
			$br[]=$ar[$i];<br />
		}<br />
		return implode(",",$br);<br />
	}<br />
	echo jiequ($str,1,5);//1和5表示截取第一个,和第5个,之间的数<br />