php正则匹配html中带class的div并选取其中内容的方法

<div class="chartInfo"> 
 <div class="line"></div>
 <div class="tideTable"> 
     <strong>潮汐表</strong>数据仅供参考
     <table width="500" border="0" cellspacing="0" cellpadding="0">
       <tbody><tr> 
  <td width="100"><p><span>潮时 (Hrs)</span></p></td> 
     <td width="100"><p>00:58</p></td>
     <td width="100"><p>05:20</p></td>
     <td width="100"><p>13:28</p></td>
     <td width="100"><p>21:15</p></td>
          </tr> 
       <tr> 
  <td><p><span>潮高 (cm)</span></p></td> 
     <td width="100"><p>161</p></td> 
     <td width="100"><p>75</p></td> 
     <td width="100"><p>288</p></td> 
     <td width="100"><p>127</p></td> 
          </tr> 
     </tbody></table> 
    <h2>时区：-1000 (东10区)  潮高基准面：在平均海平面下174CM</h2> 
       </div> 
 <div class="chart"> 
 </div> 
</div>

$ch = curl_init(); 
curl_setopt($ch, CURLOPT_URL, $url); 
curl_setopt($ch, CURLOPT_POST, 1); 
curl_setopt( $ch, CURLOPT_HEADER, 0 ); 
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, 1 ); 
curl_setopt( $ch, CURLOPT_POSTFIELDS, $data ); 
$return = curl_exec( $ch ); 
curl_close( $ch ); 
 
$regex4="/<div class=\"tideTable\".*?>.*?<\/div>/ism"; 
if(preg_match_all($regex4, $return, $matches)){ 
   print_r($matches); 
}else{ 
   echo '0'; 
}