具体实现：
index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="Action.php" method="post" enctype="multipart/form-data">
请选择您要上传的文件：<input type="file" name='myFile1' />
<input type="submit" value="上传文件" />
</form>
</body>
</html>
action.php
<?php
header('content-type:text/html;charset=utf-8');
require_once 'upload.php';
$upload=new upload('myFile1','files');
$dest=$upload->uploadFile();
echo $dest;
upload.php
<?php
class upload{
protected $fileName; //文件名
protected $maxSize; //文件最大值
protected $allowMime; //允许的文件类型
protected $allowExt; //允许的文件名
protected $uploadPath; //上传路径
protected $imgFlag; //检测是否真实图片文件
protected $fileInfo; //文件信息数组
protected $error; //检测上传文件是否出错
protected $ext; //扩展名变量
/**
* @param string $fileName
* @param string $uploadPath
* @param string $imgFlag
* @param number $maxSize
* @param array $allowExt
* @param array $allowMime
*/
public function __construct($fileName='myFile',$uploadPath='./uploads',$imgFlag=true,$maxSize=5242880,$allowExt=array('jpeg','jpg','png','gif'),$allowMime=array('image/jpeg','image/png','image/gif')){
$this->fileName=$fileName;
$this->maxSize=$maxSize;
$this->allowMime=$allowMime;
$this->allowExt=$allowExt;
$this->uploadPath=$uploadPath;
$this->imgFlag=$imgFlag;
$this->fileInfo=$_FILES[$this->fileName];
}
/**
* 检测上传文件是否出错
* @return boolean
*/
protected function checkError(){
if(!is_null($this->fileInfo)){
if($this->fileInfo['error']>0){
switch($this->fileInfo['error']){
case 1:
$this->error='超过了PHP配置文件中upload_max_filesize选项的值';
break;
case 2:
$this->error='超过了表单中MAX_FILE_SIZE设置的值';
break;
case 3:
$this->error='文件部分被上传';
break;
case 4:
$this->error='没有选择上传文件';
break;
case 6:
$this->error='没有找到临时目录';
break;
case 7:
$this->error='文件不可写';
break;
case 8:
$this->error='由于PHP的扩展程序中断文件上传';
break;
}
return false;
}else{
return true;
}
}else{
$this->error='文件上传出错';
return false;
}
}
/**
* 检测上传文件的大小
* @return boolean
*/
protected function checkSize(){
if($this->fileInfo['size']>$this->maxSize){
$this->error='上传文件过大';
return false;
}
return true;
}
/**
* 检测扩展名
* @return boolean
*/
protected function checkExt(){
$this->ext=strtolower(pathinfo($this->fileInfo['name'],PATHINFO_EXTENSION)); //pathinfo() 函数返回关于文件路径的信息，[extension]:返回文件路径中文件的类型的部分
if(!in_array($this->ext,$this->allowExt)){
$this->error='不允许的扩展名';
return false;
}
return true;
}
/**
* 检测文件的类型
* @return boolean
*/
protected function checkMime(){
if(!in_array($this->fileInfo['type'],$this->allowMime)){
$this->error='不允许的文件类型';
return false;
}
return true;
}
/**
* 检测是否是真实图片
* @return boolean
*/
protected function checkTrueImg(){
if($this->imgFlag){
if(!@getimagesize($this->fileInfo['tmp_name'])){
$this->error='不是真实图片';
return false;
}
return true;
}
}
/**
* 检测是否通过HTTP POST方式上传上来的
* @return boolean
*/
protected function checkHTTPPost(){
if(!is_uploaded_file($this->fileInfo['tmp_name'])){
$this->error='文件不是通过HTTP POST方式上传上来的';
return false;
}
return true;
}
/**
*显示错误
*/
protected function showError(){
exit('<span style="color:red">'.$this->error.'</span>');
}
/**
* 检测目录不存在则创建
*/
protected function checkUploadPath(){
if(!file_exists($this->uploadPath)){
mkdir($this->uploadPath,0777,true);
}
}
/**
* 产生唯一字符串作为文件名
* @return string
*/
protected function getUniName(){
return md5(uniqid(microtime(true),true));
}
/**
* 上传文件
* @return string
*/
public function uploadFile(){
if($this->checkError()&&$this->checkSize()&&$this->checkExt()&&$this->checkMime()&&$this->checkTrueImg()&&$this->checkHTTPPost()){
$this->checkUploadPath();
$this->uniName=$this->getUniName();
$this->destination=$this->uploadPath.'/'.$this->uniName.'.'.$this->ext;
if(@move_uploaded_file($this->fileInfo['tmp_name'], $this->destination)){
return "上传成功，".$this->destination;
}else{
$this->error='文件移动失败';
$this->showError();
}
}else{
$this->showError();
}
}
}