php实现常用文件上传类的示例

<?php
/**
 * 上传文件类
 * @param _path : 服务器文件存放路径
 * @param _allowtype : 允许上传的文件类型和所对应的mime
 * @param _file : 上传的文件信息
 */
class upload{

 private $_path;
 private $_allowtype;
 private $_file;
 /**
  * 构造函数
  * @param string : 服务器上存放上传文件的路径
  */
 function __construct( $path = '' )
 {
  $this->_path = $path;
  $this->_allowtype = array(
    // images
    'bmp' => 'image/x-ms-bmp',
    'jpg' => 'image/jpeg',
    'jpeg' => 'image/jpeg',
    'gif' => 'image/gif',
    'png' => 'image/png',
    'tif' => 'image/tiff',
    'tiff' => 'image/tiff',
    'tga' => 'image/x-targa',
    'psd' => 'image/vnd.adobe.photoshop',
    //文本
    'txt' => 'text/plain',
    'php' => 'text/x-php',
    'html' => 'text/html',
    'htm' => 'text/html',
    'js' => 'text/javascript',
    'css' => 'text/css',
    'rtf' => 'text/rtf',
    'rtfd' => 'text/rtfd',
    'py' => 'text/x-python',
    'java' => 'text/x-java-source',
    'rb' => 'text/x-ruby',
    'sh' => 'text/x-shellscript',
    'pl' => 'text/x-perl',
    'sql' => 'text/x-sql',
    //应用
    'exe' => 'application/octet-stream',
    'doc' => 'application/vnd.ms-word',
    'docx' => 'application/vnd.ms-word',
    'xls' => 'application/vnd.ms-excel',
    'ppt' => 'application/vnd.ms-powerpoint',
    'pps' => 'application/vnd.ms-powerpoint',
    'pdf' => 'application/pdf',
    'xml' => 'application/xml',
    //音频
    'mp3' => 'audio/mpeg',
    'mid' => 'audio/midi',
    'ogg' => 'audio/ogg',
    'mp4a' => 'audio/mp4',
    'wav' => 'audio/wav',
    'wma' => 'audio/x-ms-wma',
    //视频
    'avi' => 'video/x-msvideo',
    'dv' => 'video/x-dv',
    'mp4' => 'video/mp4',
    'mpeg' => 'video/mpeg',
    'mpg' => 'video/mpeg',
    'mov' => 'video/quicktime',
    'wm' => 'video/x-ms-wmv',
    'flv' => 'video/x-flv',
    'mkv' => 'video/x-matroska'
   );
 }
 /**
  * 上传函数
  * @param string : 表单元素的name 值
  * @return [type]
  */
 public function upload( $txtname = '' )
 {
  $this->_file = $_files[$txtname];
  if( $this->_file['error'] == 0){
   $filetype = end( explode('.', $this->_file['name'] ));
   $allowtype = array();
   foreach( $this->_allowtype as $item=>$value ){
    $allowtype[] = $item;
   }
   if( !in_array($filetype, $allowtype)){
    die('上传的文件格式不正确！');
   }else{
    if(move_uploaded_file($this->file['tmp_name'], ($this->path).$this->file['name']))
     {
      echo "<script>alert('上传成功!')</script>";
     }
    else
     {
      echo "<script>alert('上传失败!');</script>";
     }
   }

  }else{
   //没有正确上传
   switch ($this->file['error']){
    case 1:
     die('文件大小超过系统限制。');
     break;
    case 2:
     die('文件大小超过预定义限制。');
     break;
    case 3:
     die('文件为完全上传。');
     break;
    case 4:
     die('未上传任何文件。');
     break;
    default:
     die('上传出错');
     break;
   }
  }
 }
 //end upload
}