php正则匹配html中的带class的div，选取其中的内容

<div class="chartInfo">
				                
                <div class="line"></div>
                
                <div class="tideTable">
                    <strong>潮汐表</strong><span style="font-size:12px;font-weight:lighter;margin-left:-20px;">数据仅供参考</span>
                    <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">
					<!--<img src="http://www.cnss.com.cn/statics/images/cnss/tide/tide.jpg" width="600" height="350" title="" alt="" /> -->
                	
                </div>
               
            </div>

这是源程序里边的一部分，为了容易看懂，删减了一大部分，只取<span style="font-family: Arial, Helvetica, sans-serif;"><div class="tideTable"> div块中的内容</span>

<span style="font-family: Arial, Helvetica, sans-serif;">首页先用file_get_content或curl获取内容部分，我用的是curl。</span>

<span style="font-family: Arial, Helvetica, sans-serif;"><span style="white-space:pre"></span><span style="white-space:pre">		</span>$ch = curl_init();
<span style="white-space:pre">		</span>curl_setopt($ch, CURLOPT_URL, $url);
<span style="white-space:pre">		</span>curl_setopt($ch, CURLOPT_POST, 1);
<span style="white-space:pre">		</span>curl_setopt( $ch, CURLOPT_HEADER, 0 );
<span style="white-space:pre">		</span>curl_setopt( $ch, CURLOPT_RETURNTRANSFER, 1 );
<span style="white-space:pre">		</span>curl_setopt( $ch, CURLOPT_POSTFIELDS, $data );
<span style="white-space:pre">		</span>$return = curl_exec( $ch );
<span style="white-space:pre">		</span>curl_close( $ch );
<span style="white-space:pre">		</span>
<span style="white-space:pre">		</span>$regex4="/<div class=\"tideTable\".*?>.*?<\/div>/ism";
<span style="white-space:pre">		</span>if(preg_match_all($regex4, $return, $matches)){
            <span style="white-space:pre">		</span> print_r($matches);
<span style="white-space:pre">		</span>}else{
<span style="white-space:pre">			</span>echo '0';
<span style="white-space:pre">		</span>}</span>

<span style="font-family:Arial, Helvetica, sans-serif;">这样就可以了，不多解释，懂PHP的看代码，打印看一下效果。</span>

</pre><pre name="code" class="html">

</pre><pre name="code" class="html">