PHP检测URL是否被百度收录

<?php

header('Content-type:text/html;charset=utf-8');

function checkBaidu($url){
$url='http://www.baidu.com/s?wd='.$url;

$curl = curl_init();
curl_setopt($curl,CURLOPT_URL,$url);
curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
$rs = curl_exec($curl);
curl_close($curl);

$arr = parse_url($url);

if(strpos($arr['query'],'http://')){
$arr['query'] = str_replace('http://','',str_replace('wd=','',$arr['query']));
} else{

$arr['query'] = str_replace('wd=','',$arr['query']);
}

if(strpos($arr['query'],'?')){
$str = strstr($arr['query'],'?');
$arr['query'] = str_replace($str,'',$arr['query']);
}
if(strpos($arr['query'],'/')){
$narr = explode('/',$arr['query']);
$arr['query'] = $narr[0];
}

if(strpos($rs,'<b>'.$arr['query'].'</b>')){
return '收录';
} else{
return '未收录';
}
}
echo checkBaidu('www.sjyhome.com');