实例简单php图片上传类

class Uploadimg{
 private $_fileName="";         //文件域名称 如 'userfile'
 private $_uploadDir = '';       //上传路径 如 ./upload/
 
 /*上传参数配置*/
 private $_config = array(
  'type'=>array('image/jpeg','image/jpg',
    'image/pjpeg','image/gif'),         //上传的类型
  'size'=>1,                     //文件最大容量单位是M
  'width'=>1000,                   //图片的最大宽度
  'height'=>800                   //图片的最大高度
 );
 
 /**
  * 构造函数
  *
  * @param string $fileName
  * @param string $uploadDir
  * @param array $config
  */
 function __construct($fileName,$uploadDir,$config='')
 {
  $this->_fileName = $fileName;
  $this->_uploadDir = $uploadDir;
  if($config == "" or empty($config) or !is_array($config)){
   $this->_config = $this->_config;
  }else{
   $this->_config = $config;
  }
 }
 
 /**
  * 检测容量是否超过
  *
  * @return boolean
  */
 function checkSize()
 {
  if($_FILES[$this->_fileName]['size'] > $this->_config['size']*1024*1024){
   return false;
  }else{
   return true;
  } 
 }
 
 /**
  * 获取图片信息
  *
  * @return boolean
  */
 function getInfo()
 {
  return @getimagesize($_FILES[$this->_fileName]['tmp_name']);
 }
 
 /**
  * 检测后缀名
  *
  * @return boolean
  */
 function checkExt()
 {
  $imageInfo = $this->getInfo();
  if(in_array($imageInfo['mime'],$this->_config['type'])){
   return true;
  }else{
   return false;
  }
 }
 
 /**
  * 获取后缀名
  *
  * @return boolean
  */
 function getExt()
 {
  $imageInfo = $this->getInfo();
  switch($imageInfo['mime']){
   case 'image/jpeg':$filenameExt = '.jpg';break;
   case 'image/jpg':$filenameExt = '.jpg';break;
   case 'image/pjpeg':$filenameExt = '.jpg';break;
   case 'image/gif':$filenameExt = '.gif';break;
   default:break;
  }
  return $filenameExt;  
 }
 
 /**
  * 检测尺寸
  *
  * @return boolean
  */
 function checkWh()
 {
  $imageInfo = $this->getInfo();
  if(($imageInfo[0] > $this->_config['width']) or ($imageInfo[1] > $this->_config['height'])){
   return false;
  }else{
   return true;
  }
 }
 
 /**
  * 上传一张图片
  *
  * @return string or int
  */
 function uploadSingleImage()
 {
  if($this->checkSize() == false){
   return (-3); /*上传容量过大*/
   exit();
  }  
  if($this->checkExt() == true){
   $filenameExt = $this->getExt();
  }else{
   return (-2);  /*上传格式错误*/
   exit();
  }
  if($this->checkWh() == false){
   return (-1);  /*上传图片太宽或太高*/
   exit();
  }
  $file_new_name = date('YmdHis').$filenameExt;
  $file_new_name_upload = rtrim($_SERVER['DOCUMENT_ROOT'],'/').$this->_uploadDir.$file_new_name;
  if(@move_uploaded_file($_FILES[$this->_fileName]['tmp_name'],$file_new_name_upload)){
   return $file_new_name;
  }else{
   return (0); /*上传失败*/
  } 
 }
 
 /**
  * 删除图片
  *
  * @param string $imageName
  * @return boolen
  */
 function delImage($imageName)
 {
  $path = rtrim($_SERVER['DOCUMENT_ROOT'],'/').$this->_uploadDir.$imageName;
  if(unlink($path) == true){
   return true;
  }else{
   return false;
  }
 }
}