Question

我是rss feed和php分页的新手。我尝试解析rss Feed并在不同的页面上显示每个Feed详细信息。我从http://www.phpeasystep.com/phptu/29.html复制并粘贴了分页代码。当我在localhost上运行index.php时，不会显示任何内容。

使用curl下载rss feed没有问题。我也尝试过print_r（$ data），数据显示正常。

有人能指出我出错的地方吗？谢谢。

我的代码：

<?php
if (function_exists("curl_init")){
    $ch=curl_init();
    curl_setopt($ch,CURLOPT_URL,"http://feeds.feedburner.com/rb286");
    curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
    $data=curl_exec($ch);
    curl_close($ch);
    $doc=new SimpleXmlElement($data);
    //print_r($doc);
}

function parseRSS($xml){
    $items=$xml->xPath('/rss/channels/item');

    $count=count($items);

    // How many adjacent pages should be shown on each side?
    $adjacents =3;


    $total_pages = $count;

    /* Setup vars for query. */
    $targetpage = "index.php";  //your file name  (the name of this file)
    $limit = 1;                                 //how many items to show per page
    $page = $_GET['page'];
    if($page) 
        $start = ($page - 1) * $limit;          //first item to display on this page
    else
        $start = 0;                             //if no page var is given, set start to 0


    /* Setup page vars for display. */
    if ($page == 0) $page = 1;                  //if no page var is given, default to 1.
    $prev = $page - 1;                          //previous page is page - 1
    $next = $page + 1;                          //next page is page + 1
    $lastpage = ceil($total_pages/$limit);      //lastpage is = total pages / items per page, rounded up.
    $lpm1 = $lastpage - 1;                      //last page minus 1

    /* 
        Now we apply our rules and draw the pagination object. 
        We're actually saving the code to a variable in case we want to draw it more than once.
    */
    $pagination = "";
    if($lastpage > 1)
    {   
        $pagination .= "<div class=\"pagination\">";
        //previous button
        if ($page > 1) 
            $pagination.= "<a href=\"$targetpage?page=$prev\">� previous</a>";
        else
            $pagination.= "<span class=\"disabled\">� previous</span>"; 

        //pages 
        if ($lastpage < 7 + ($adjacents * 2))   //not enough pages to bother breaking it up
        {   
            for ($counter = 1; $counter <= $lastpage; $counter++)
            {
                if ($counter == $page)
                    $pagination.= "<span class=\"current\">$counter</span>";
                else
                    $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                 
            }
        }
        elseif($lastpage > 5 + ($adjacents * 2))    //enough pages to hide some
        {
            //close to beginning; only hide later pages
            if($page < 1 + ($adjacents * 2))        
            {
                for ($counter = 1; $counter < 4 + ($adjacents * 2); $counter++)
                {
                    if ($counter == $page)
                        $pagination.= "<span class=\"current\">$counter</span>";
                    else
                        $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                 
                }
                $pagination.= "...";
                $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
                $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";       
            }
            //in middle; hide some front and some back
            elseif($lastpage - ($adjacents * 2) > $page && $page > ($adjacents * 2))
            {
                $pagination.= "<a href=\"$targetpage?page=1\">1</a>";
                $pagination.= "<a href=\"$targetpage?page=2\">2</a>";
                $pagination.= "...";
                for ($counter = $page - $adjacents; $counter <= $page + $adjacents; $counter++)
                {
                    if ($counter == $page)
                        $pagination.= "<span class=\"current\">$counter</span>";
                    else
                        $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                 
                }
                $pagination.= "...";
                $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
                $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";       
            }
            //close to end; only hide early pages
            else
            {
                $pagination.= "<a href=\"$targetpage?page=1\">1</a>";
                $pagination.= "<a href=\"$targetpage?page=2\">2</a>";
                $pagination.= "...";
                for ($counter = $lastpage - (2 + ($adjacents * 2)); $counter <= $lastpage; $counter++)
                {
                    if ($counter == $page)
                        $pagination.= "<span class=\"current\">$counter</span>";
                    else
                        $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                 
                }
            }
        }

        //next button
        if ($page < $counter - 1) 
            $pagination.= "<a href=\"$targetpage?page=$next\">next �</a>";
        else
            $pagination.= "<span class=\"disabled\">next �</span>";
        $pagination.= "</div>\n";       
    }

        foreach($items as $item){
              echo("<a href='".$item[0]->link."'>".$item[0]->title."</a>");
        }
}
if (isset($doc->channel))parseRSS($doc);

?>
<?php 
 echo($pagination);
?>
</body>

Answer 1

好的，这个代码存在一些问题：

首先，在函数内创建变量$pagination;，因此在全局范围外不可用。快速解决此问题的方法是：

在页面开头添加：

<?php 
$pagination = '';

在函数内添加：

function parseRSS($xml){
    global $pagination;

接下来Xpath位置错误

改变：

$items=$xml->xPath('/rss/channels/item');

进入

$items=$xml->xPath('/rss/channel/item');

这些更改应该会为您提供一些输出以启动，我认为您的分页存在更多问题，但是一旦您有一些输出，您应该设法对其进行排序。

编辑： 要获得所需的链接，您应该更改：

<?php  
foreach($items as $item){
    echo("<a href='".$item[0]->link."'>".$item[0]->title."</a>");
}

进入：

<?php  
foreach($items as $key => $item){
    if( ( $key >= $start) && ($key < $start + $limit) ){
        echo("<a href='".$item[0]->link."'>".$item[0]->title."</a>");
    }
}

Answer 2

DonSeba，你的第二个foreach循环工作正常。每个链接都在不同的页面上显示良好。但是，请告诉我你的if语句有两个条件的目的是什么？我尝试了以下只有1 if条件，它也可以正常工作：

foreach($items as $key => $item){ 
//if( ( $key >= $start) && ($key < $start + $limit) ){ //your if statement
  if ($key==$start){
    echo("<a href='".$item[0]->link."'>".$item[0]->title."</a>"); 
     } 
 }

谢谢。

用php分页显示rss feed

2 个答案: