尽管更新URL，顺序cURL仍返回相同的内容

Question

我正在尝试编写一个脚本，以便从受密码保护的网站中删除几页。

我们的想法是从他们的产品数据库中提取有关提交的股票代码的信息，以生成并打印出结果（最终直接导入我自己的数据库，但目前只是在屏幕上打印结果）。

我的功能如下：

function LookupProduct($ItemCodes) {    

//set a temp file name for the login cookie
    $tmp_fname = "tmp/".md5(date('D F d')).".cookie";
    $tmp_fname = realpath($tmp_fname);

//reset/declare the functions output
    $return = '';

// build post data from form
    $fields = array(
        'UserName' => urlencode("username"),
        'Password' => urlencode("password"),
    );
    $fieldString='';
    foreach($fields as $key=>$value) { 
        $fieldString .= $key.'='.$value.'&';
    }
    rtrim($fieldString, '&');

//initialise the curl session
    $ch = curl_init();

//set options for curl login 
    $loginurl = "https://suppliers-website/login/";
    curl_setopt($ch,CURLOPT_URL, $loginurl);
    curl_setopt($ch,CURLOPT_FOLLOWLOCATION, 1);
    curl_setopt($ch,CURLOPT_COOKIESESSION, true);
    curl_setopt($ch,CURLOPT_POST, count($fields));
    curl_setopt($ch,CURLOPT_SSL_VERIFYHOST, false);
    curl_setopt($ch,CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch,CURLOPT_POSTFIELDS, $fieldString);
    curl_setopt($ch,CURLOPT_COOKIEJAR, $tmp_fname);
    curl_setopt($ch,CURLOPT_COOKIEFILE, $tmp_fname);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER, true);

//do the actual login, generate cookie
    $result = curl_exec($ch);

//build array of codes to lookup
    $codes=explode(",", $ItemCodes);

//lookup each code in the array
    foreach($codes as $code) {

        //set the product page to curl
        $lookupUrl = "https://suppliers-website/product/".$code;        
        curl_setopt($ch,CURLOPT_URL, $lookupUrl);

        //load product page html into $lookupcontent
        unset($lookupcontent);
        $lookupcontent = curl_exec($ch);

        //if we have a valid page, then go ahead and pluck the data
        if (strlen($lookupcontent) < 100) {
            echo "<li>Error logging in: <blockquote>".$lookupcontent."</blockquote></li>";
        } else {

            //load product page html into a DOM
            unset($dom);
            unset($xpath);
            $dom = new DOMDocument;
            $dom->loadHTML($lookupcontent);
            $xpath = new DOMXPath($dom);

            //find the image src
            unset($imgnames);
            foreach($dom->getElementsByTagName('a') as $node) {
                if (strpos($node->getAttribute('href'),'StockLoRes') !== false) {
                    $imgnames = explode("=", $node->getAttribute('href'));
                    $imgname = $imgnames[1];

                    $filelocation = $node->getAttribute('href');
                }
            }

            //set the image to curl
            $imglink = "https://suppliers-website/login/".$filelocation;
            curl_setopt($ch,CURLOPT_URL,$imglink);  

            //curl the image
            unset($curlimage);
            $curlimage = curl_exec($ch);

            //save the image locally
            unset($saveimage);
            $saveimage = fopen('tmp/'.$imgname, 'w');
            fwrite($saveimage, $curlimage);
            fclose($saveimage);

            // find the product description
            unset($results);
            $classname = 'ItemDetails_Description';
            $results = $xpath->query("//*[@class='" . $classname . "']");

            if ($results->length > 0) {
                $description = $results->item(0)->nodeValue;
                $description = strip_tags($description);
                $description = str_replace("•", "", $description);
            }

            //find the price
            unset($pricearray);

            foreach($dom->getElementsByTagName('div') as $node) {
                if (strpos($node->nodeValue,'£') !== false) {
                    $pricearray[] = $node->nodeValue;
                }
            }
            $pricearray=array_reverse($pricearray);
            $price = $pricearray[0];
            $price = str_replace("£", "", $price);

            //find the title
            unset($results);
            $classname = 'ItemDetails_ItemName';
            $results = $xpath->query("//*[@class='" . $classname . "']");

            if ($results->length > 0) {
                $title = $results->item(0)->nodeValue;
            }

            //find the publisher
            unset($results);
            $classname = 'ItemDetails_Publisher';
            $results = $xpath->query("//*[@class='" . $classname . "']");

            if ($results->length > 0) {
                $publisher = $results->item(0)->nodeValue;
            }
        }

        //add all the values to the data to be returned
        $return .= '<div style="border:1px solid grey;margin:20px;float:left;">';
        $return .= "<a href='tmp/".$imgname."'>";
        $return .= "<img src='tmp/".$imgname."' width='100' align='left' /></a>";
        $return .=  "<h1>"  .$title     ."</h1>";
        $return .=  "<h3>"  .$publisher ."</h3>";
        $return .=  "<h2>£" .$price     ."</h2>";
        $return .=  "<h4>"  .$description."</h2>";
        $return .= '</div><br clear="all" />';

    }

    //echo out the data
    echo $return;

    //close connection
    curl_close($ch);
}

我正在使用以下内容触发它：

if(isset($_POST['ItemCodes'])) {  
    $code=$_POST['ItemCodes'];
    $code=str_replace("\n\r", ",", $code);
    $code=str_replace("\r", ",", $code);
    echo "ItemCodes: ".$code;
    echo LookupProduct($code);
}

该脚本可以成功登录，保存cookie并从页面获取信息，但如果我尝试请求多个页面，则脚本无法按预期工作，而是返回同一产品的3个实例。我是否未能在某处重置变量？我已尝试取消所有设置，但我仍然只使用相同的产品三次，就好像我的功能只能使用一次。