PHP抓取天气预报的代码

$strurl = " http://www.cma.gov.cn/tqyb/weatherdetail/54511.html " ;
$strhtmlarray = file ( $strurl );
$strlinehtml =   implode ( '' ,   $strhtmlarray ); 
eregi ( " 3天预报(.*)指数查询 " ,   $strlinehtml ,   $head );