Краткое описание Примеров работы с файлами PHP [Загрузка файлов, Загрузка, Подкачка]

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// for example
move_uploaded_file($_FILES['myfile']['tmp_name'], 'd:/upload/');

$max_size = 3 * 1024 * 1024; // Constraint 3M
if($_FILES['myfile']['size'] > $max_size){
  Echo'uploads pictures larger than 3M';
  exit;
}
// upload
if(move_uploaded_file($_FILES['myfile']['tmp_name'], $path)){
  Echo'upload success';
} else {
  Echo'failed upload';
}

// To prevent users from modifying file suffixes, an extended Finfo implementation of PHP is used
# 1. Open PHP extension in php.ini
extension=php_fileinfo.dll
# 2. Using Extended Classes to Get the Real Type of Uploaded Files
$finfo = new Finfo(FILEINFO_MIME_TYPE);
$mime_type = $finfo->file($_FILES['myfile']['tmp_name']);

/*
 * Description: File upload class
 * Author: SGW
 * Time: 2018-7-31
 */
class Upload
{
  // Membership attributes
  Private $_maxsize = 2 * 1024 * 1024; // Upload file maximum range 2M
  Private $_upload_path ='upload/'; // Upload file save path
  Private $_prefix='odshen_'; // prefix of filename
  Private $allow_type = array ('.jpg','.png','.gif','.jpeg'); and // file type that allows upload
  private $allow_mime_type = array('image/jpeg','image/png','image/gif','image/jpg');
  /**
   * Set Sets Private Properties
   *@ param [str] $p [attribute name]
   *@ param [mix] $v [assign values to attributes]
   */
  public function __set($p,$v)
  {
    if(property_exists($this,$p)){
      $this -> $p = $v;
    }
  }
  /**
   * get gets private properties
   *@ param [str] $p [attribute name]
   */
  public function __get($p)
  {
    if(property_exists($this,$p)){
      return $this -> $p;
    }
  }
  /**
   * Upload File Method
   *@ param [mix] $file [uploaded file]
   */
  public function doUpload($file)
  {
    // Judging the size of files uploaded by users
    $max_size = $this - > Max size; // maximum constraint is 2M
    if($file['size'] > $max_size){
      Echo'upload files too large, re-upload';
      exit;
    }
    # Prevent uploaded files from being overwritten
    $prefix = $this->_prefix;
    // File name unique
    $filename = uniqid($prefix,true);
    // File suffix to intercept strrchr after the last point from the uploaded file name
    $ext = strrchr($file['name'],'.');
    // Subdirectory saves uploaded files and saves them in date format
    $sub_path = $this->_upload_path.date('Ymd').'/';    // upload/20180731/
    # If the current directory does not exist, you need to create the absolute path first.
    $now_path = __DIR__.'/';
    $now_path = str_replace('\','/',$now_path.$sub_path);
    if(!is_dir($now_path)){
      mkdir($now_path,0777,true);
    }
    # Restrict file types uploaded by users
    if(!in_array($ext,$this->allow_type)){
      Echo'File type is not supported';
      exit;
    }
    # To prevent users from modifying the suffix of files, an extended Finfo implementation of PHP is used to obtain the exact type of each file in the network.
    $finfo = new Finfo(FILEINFO_MIME_TYPE);
    $mime_type = $finfo -> file($file['tmp_name']);
    if(!in_array($mime_type,$this->allow_mime_type)){
      Echo'File type is not supported';
      exit;
    }
    // Parametric 1: Files to be moved (temporary files)
    // Parametric 2: Destination
    // Returns the result Boolean type
    if(move_uploaded_file($file['tmp_name'],$now_path.$filename.$ext)){
      // If the upload succeeds in returning the uploaded file address to facilitate the use of the picture elsewhere, you need to be able to find the picture.
      return $sub_path . $filename.$ext;
    }else{
      // echo'failed upload';
      return false;
    }
  }
}

// First receive the name of the file passed in the address bar, that is, which file is downloaded.
$filename = $_GET['filename'];
if($filename==''){
  Echo'File not found, download failed';
  exit;
}
// Path of Stitching Files
$full_name = 'img/'.$filename;
// The picture is GBK coded under Windows system, and the PHP file is UTF-8 coded.
// Usually you need to change the encoding of the PHP file to GBK first
$full_name = iconv('utf-8','gbk',$full_name);
$filesize = filesize($full_name);
# [Main] Start downloading and tell the browser through the header header that I'm responding to file resources.
// The returned file
header("Content-type: application/octet-stream");
// Returns by byte size
header("Accept-Ranges: bytes");
// Display file size
header("Content-Length: $filesize");
// Here the client pop-up dialog box, the corresponding file name
header("Content-Disposition: attachment; filename=".$filename);
// Start reading file resources and respond to browsers
$fp = fopen($full_name,'r');
while(!feof($fp)){
  $data = fread($fp,1024);
  echo $data;
}
fclose($fp);

/*
 * Paging Display Data
 */
class Page
{
  Private $_total; // Total number of records
  Private $_pagesize; // Number of records displayed per page
  Private $_pagenow; // Current page number
  Private $_url; // The URL address that jumps when clicking on a hyperlink
  /**
   * Set Sets Private Properties
   *@ param [str] $p [attribute name]
   *@ param [mix] $v [assign values to attributes]
   */
  public function __set($p,$v)
  {
    if(property_exists($this,$p)){
      $this -> $p = $v;
    }
  }
  /**
   * get gets private properties
   *@ param [str] $p [attribute name]
   */
  public function __get($p)
  {
    if(property_exists($this,$p)){
      return $this -> $p;
    }
  }
  // Dynamic creation of paging navigation bar
  public function create()
  {
    // Define Home Button
    // Current page highlighting
    $first_active = $this->_pagenow == 1?'active':'';
    $url = $this -> _url.'?page=';
    $first = 1;
    $PAGE = <<
        
  Home page
HTML;
    // Create intermediate paging navigation buttons
    // First calculate how many pages are currently available = total data / data displayed per page
    $page_count = ceil($this -> _total / $this ->_pagesize);
    for($i=$this->_pagenow-3; $i<=$this->_pagenow+3; $i++){
      $active = $this->_pagenow == $i?'active':'';
      if($i <= 1 || $i>= $page_count){
        Continue; // Jump out of this cycle
      }
      $PAGE .= <<$i
HTML;
    }
    // Define the tail button
    $last_active = $this->_pagenow == $page_count?'active':'';
    $PAGE .= <<  end page
    
HTML;
    // Returns the created paging navigation bar
    return $PAGE;
  }
}