具有下一个和上一个功能的画廊

Question

作为我学习 php 的第一个真正项目，我正在开发一个图片库。我无法以某种方式解决的问题是使用“上一个”按钮。我的“下一个”功能从文件夹中抓取接下来的 6 张图像并将它们发布到页面上，我的上一个功能反向执行此操作.. 但这是不正确的，你能帮忙吗？哦，这个代码是草率的初学者代码，所以我很高兴提示:)

<?php 
session_start();

if(session_id() == '') {
 $_SESSION["count"] = 0;
}

function PostHTML($id, $file) {
    if($id==0) {
           echo "<div class=\"item\"><div class=\"well\"><img 
           class=\"img-responsive\" src=\"$file\" alt=\"\"><p>blahblahblah xxxxxx</p></div></div>";
    }else{
           echo "<div class=\"item\"><div class=\"well\"><video autoplay 
           loop class=\"img-responsive\"><source src=\"$file\" type=\"video/mp4\"></video></div></div>";
    }
}

function next_img() {

   $dir = "images/src/*.*"; 

   $files = array();
   $start = $_SESSION["count"];
   $end = $_SESSION["count"]+6;

   $y=0;
       foreach(glob($dir) as $file) {
          $files[$y] = $file;
          $y++;
       }

for($i=$start; $i < $end; $i++){
   if(pathinfo($files[$i], PATHINFO_EXTENSION)=="jpg") { 
     PostHTML(0,$files[$i]); 
   } else { 
     PostHTML(1,$files[$i]); }
}


$_SESSION["count"]+=6;


}

function prev_img() {
   $dir = "images/src/*.*"; 

   $files = array();
   $start = $_SESSION["count"]-1; 
   $end = $_SESSION["count"]-6;

   $y=0;
   foreach(glob($dir) as $file) {
        $files[$y] = $file; //100 files
        $y++;  
    }

   for ($i = $start; $i > $end; $i--) {
        if(pathinfo($files[$i], PATHINFO_EXTENSION)=="jpg") { 
         PostHTML(0,$files[$i]); 
       } else { 
         PostHTML(1,$files[$i]); 
       }   
   }
   $_SESSION["count"]-=6;
}

?>

Answer 1

如果我要做这样的事情，我可能会创建一个文件控制器类来管理我可能需要的所有文件操作。

<?php




class FileController
{

    private $_dir = "DIR";
    private $files;
    private $current;

    function__construct()
    {

        $current = 0;

        $files = scandir($_dir); // scans the dir to get a list of file names
        if(!$files) echo "Failed To Load Files"; // failed to load files
        else 
        {
            $this->file = $files; // objects propery contains all file names in array;
        }

    }


    function PostHTML($fileName) {


        $src = $this->_dir + "/" + $fileName;

        if(!$fileName)
        {
                return "<div class=\"item\"><div class=\"well\"><img 
           class=\"img-responsive\" src=\"$src\" alt=\"\"><p>blahblahblah xxxxxx</p></div></div>";
        }
        else
        {

            return "<div class=\"item\"><div class=\"well\"><video autoplay 
           loop class=\"img-responsive\"><source src=\"$src\" type=\"video/mp4\"></video></div></div>";
        }
}




    function nextImg()
    {

        $current = $this->getCurrent();
        $end = $current + 6;
        $this->setCurrent($end);
        $files = $this->files;

        $html = "";
        for($i = $current; $i<= $end; $i++)
        {
            $html += postHtml($files[$i]);
        }

        echo $html;


    }


    function prevImg()
    {

        $current = $this->getCurrent();
        $end = $current - 6;
        $this->setCurrent($end);
        $files = $this->files;

        $html = "";
        for($i = $current; $i>= $end; $i--)
        {
            $html += postHtml($files[$i]);
        }

        echo $html;



    }

    function getCurrent()
    {
        return $_SESSION['current'];

    }

    function setCurrent($current)
    {
            $_SESSION['current'] = $current;

    }






}


?>