thinkphp实现图片上传功能

<form action="__URL__/addChk" method="post" enctype="multipart/form-data"> 
 <table cellspacing="1" cellpadding="2" width="99%" align="center" border="0"> 
  <tbody> 
   <tr> 
   <th align="left" colspan="2" height="25">添加新游戏</th> 
   </tr> 
   <tr> 
   <td width="17%" height="23">游戏名称</td> 
   <td width="83%"><strong><input type="text" name="gamename" /></strong></td> 
   </tr> 
   <tr> 
   <td height="23">游戏图片</td> 
   <td ><input type="file" name="gameimg"/></td> 
   </tr> 
   <tr> 
   <td width="17%" height="23">游戏简介<span></span></td> 
   <td width="83%"><textarea name="gameinfo" cols="30" rows="5"></textarea></td> 
   </tr> 
   <tr> 
   <td height="23">游戏地址：</td> 
   <td> 
   <input type="text" name="gamelink"/></td> 
   </tr> 
   <tr> 
   <td height="23" colspan="2" ><input type="submit" value="添加" />  
    <input type="reset" value="重新填写"/></td> 
   </tr> 
  </tbody> 
  </table> 
</form>

class AddAction extends Action{ 
 /** 
 * 说明：ThinkPHP文件上传测试函数 
 * 版本：1.0 

 */ 
 public function addChk(){ 
   //导入图片上传类 
   import("ORG.Net.UploadFile"); 
   //实例化上传类 
   $upload = new UploadFile(); 
   $upload->maxSize = 3145728; 
   //设置文件上传类型 
   $upload->allowExts = array('jpg','gif','png','jpeg'); 
   //设置文件上传位置 
   $upload->savePath = "./Public/Uploads/";//这里说明一下，由于ThinkPHP是有入口文件的，所以这里的./Public是指网站根目录下的Public文件夹 
   //设置文件上传名(按照时间) 
   $upload->saveRule = "time"; 
   if (!$upload->upload()){ 
    $this->error($upload->getErrorMsg()); 
   }else{ 
    //上传成功，获取上传信息 
    $info = $upload->getUploadFileInfo(); 
   } 
 
   //保存表单数据，包括上传的图片 
   $game = M("Game"); 
   $game->create(); 
   $savename = $info[0]['savename']; 
   //$savepath = $info[0]['savepath']; 
   //$aa = $savepath.$savename; 
   //dump($aa); 
   $imgurl = "http://demo.dutycode.com/Public/Uploads/".$savename;//这里是设置文件的url注意使用.不是+ 
   //dump($imgurl); 
   $data['gamename'] = $_POST['gamename']; 
   $data['gameimg'] = $imgurl; 
   $data['gameinfo'] = $_POST['gameinfo']; 
   $data['gamelink'] = $_POST['gamelink']; 
   $data['publishtime'] = date("Y-m-d H:i:s"); 
   $res = $game->add($data);//写入数据库 
   if ($res){ 
    $this->redirect("addGame","",2,"添加成功！两秒后跳回"); 
   }else{ 
    $this->redirect("addGame","",2,"失败！两秒后跳回"); 
   } 
}