class upload_class{
private $ptname;    //上传表单名称;
private $udname;    //是否以月份建立子目录(0为否,其他为真);
private $ufname;    //是否以php?name=%CA%B1%BC%E4>时间建立文件名(0为否,其他为真);
private $ultype;    //上传文件类型;
private $ulsize;    //上传文件大小;
private $ulname;    //输出文件名称;
private $ulpath;    //输出文件路径;
private $wm;     //水印附加(0为不加,其他为加);
private $wmtype;    //水印类型(0为文字,其他为图片);
private $wmpic;     //水印图片;
private $wmpicquality;   //图片质量;
private $wmpictrans;   //图片透明;
private $wmstr;     //水印字符;
private $wmstrsize;    //字符大小;
private $wmstrfont;    //字符字体;
private $wmstrcolor;   //字符颜色;
private $wmpos;     //水印位置(1为顶端居左,2为顶端居中,3为顶端居右……);
function __construct($ptname=upfile,$udname=1,$ufname=1,$ultype=array(image/jpg,image/jpeg,image/png,image/pjpeg,image/gif,image/bmp,image/x-png),$wm=1,$wmtype=1,$wmpic=images/wm.gif,$ulsize=2097152,$ulpath=images/temp/,$wmpictrans=20,$wmpicquality=80,$wmstr=DONLINE,$wmstrsize=5,$wmstrfont=./font/cour.ttf,$wmstrcolor=#ff0000,$wmpos=9){
  $this->ptname=$_FILES[$ptname];
  $this->udname=$udname;
  $this->ufname=$ufname;
  $this->ultype=$ultype;
  $this->ulsize=$ulsize;
  $this->ulpath=$ulpath;
  $this->wm=$wm;
  $this->wmtype=$wmtype;
  $this->wmpic=$wmpic;
  $this->wmpicquality=$wmpicquality;
  $this->wmpictrans=$wmpictrans;
  $this->wmstr=$wmstr;
  $this->wmstrsize=$wmstrsize;
  $this->wmstrfont=$wmstrfont;
  $this->wmstrcolor=$wmstrcolor;
  $this->wmpos=$wmpos;
}
function uploadfun(){
  if($_SERVER[REQUEST_METHOD]==POST){
   if(!is_uploaded_file($this->ptname[tmp_name]))$this->errorfun(上传失败！);
   if(!in_array($this->ptname[type],$this->ultype))$this->errorfun(不支持的文件类型！);
   if($this->ulsize<$this->ptname[size])$this->errorfun(文件太大！);
   if($this->udname){date_default_timezone_set(UTC);$this->ulpath=$this->ulpath.month_.date(Ym)./;}
   else{$this->ulpath=$this->ulpath;}
   $this->createfun($this->ulpath);
   if($this->ufname){$t=pathinfo($this->ptname[name]);$this->ulname=$this->ulpath.time()...$t[extension];}
   else{$this->ulname=$this->ulpath.$this->ptname[name];}
   if(file_exists($this->ulname))$this->errorfun(该文件已存在！);
   if(!move_uploaded_file($this->ptname[tmp_name],$this->ulname))$this->errorfun(移动文件错误！);
   $this->wmfun();
   $this->errorfun(上传成功！);
  }
}
function createfun($d){
  if(!file_exists($d)){$this->createfun(dirname($d));mkdir($d);}
}
function wmfun(){
  if($this->wm){
   if(file_exists($this->ulname)){
    $groundimg=getimagesize($this->ulname);
    $ow=$groundimg[0];
    $oh=$groundimg[1];
    switch($groundimg[2]){
     case 1:$g=imagecreatefromgif($this->ulname);break;
     case 2:$g=imagecreatefromjpeg($this->ulname);break;
     case 3:$g=imagecreatefrompng($this->ulname);break;
     case 4:$g=imagecreatefromwbmp($this->ulname);break;
     default:$this->errorfun(不支持的背景图片类型！);
    }
   }
   else{$this->errorfun(背景图片不存在！);}
   if(file_exists($this->wmpic)){
    $wmimg=getimagesize($this->wmpic);
    $ww=$wmimg[0];
    $wh=$wmimg[1];
    switch($wmimg[2]){
     case 1:$w=imagecreatefromgif($this->wmpic);break;
     case 2:$w=imagecreatefromjpeg($this->wmpic);break;
     case 3:$w=imagecreatefrompng($this->wmpic);break;
     case 4:$w=imagecreatefromwbmp($this->wmpic);break;
     default:$this->errorfun(不支持的水印图片类型！);
    }
   }
   else{$this->errorfun(水印图片不存在！);}
   switch($this->wmtype){
    case 0:$tp=imagettfbbox(ceil($this->wmstrsize*2.5),0,$this->wmstrfont,$this->wmstr);$ww=$tp[2]-$tp[6];$wh=$tp[3]-$tp[7];unset($tp);break;
    case 1:$ww=$ww;$wh=$wh;break;
    default:$ww=$ww;$wh=$wh;break;
   }
   if($ow<$ww || $oh<$wh)$this->errorfun(背景图片太小！无法生成水印！);
   switch($this->wmpos){  
    case 0:$x=rand(0,($ow-$ww));$y=rand(0,($oh-$wh));break;//随机
          case 1:$x=0;$y=0;break;//1为顶端居左     
          case 2:$x=($ow-$ww)/2;$y=0;break;//2为顶端居中     
          case 3:$x=$ow-$ww;$y=0;break;//3为顶端居右     
          case 4:$x=0;$y=($oh-$wh)/2;break;//4为中部居左     
          case 5:$x=($ow-$ww)/2;$y=($oh-$wh)/2;break;//5为中部居中   
          case 6:$x=$ow-$ww;$y=($oh-$wh)/2;break;//6为中部居右     
          case 7:$x=0;$y=$oh-$wh;break;//7为底端居左  
          case 8:$x=($ow-$ww)/2;$y=$oh-$wh;break;//8为底端居中     
          case 9:$x=$ow-$ww;$y=$oh-$wh;break;//9为底端居右     
          default:$x=rand(0,($ow-$ww));$y=rand(0,($oh-$wh));break;//随机         
      }
   imagealphablending($g, true);
   switch($this->wmtype){
    case 0:
    if($this->wmstrcolor){$R=hexdec(substr($this->wmstrcolor,1,2));$G=hexdec(substr($this->wmstrcolor,3,2));$B=hexdec(substr($this->wmstrcolor,5));}
    else{$this->errorfun(水印文字颜色不存在！);}
    imagestring($g,$this->wmstrfont,$x,$y,$this->wmstr,imagecolorallocate($g,$R,$G,$B));break;
    case 1;imagecopymerge($g,$w,$x,$y,0,0,$ww,$wh,$this->wmpictrans);break;
    default:imagecopymerge($g,$w,$x,$y,0,0,$ww,$wh,$this->wmpictrans);break;
   }
   @unlink($this->ulname);
   switch($groundimg[2]){
          case 1:imagegif($g,$this->ulname);break;
          case 2:imagejpeg($g,$this->ulname,$this->wmpicquality);break;
          case 3:imagepng($g,$this->ulname);break;
    case 4:imagewbmp($g,$this->ulname);break;
          default:$this->errorfun(生成图片失败！);
   }
   if(isset($wmimg))unset($wmimg);
      if(isset($w))imagedestroy($w);
      unset($groundimg);
      imagedestroy($g);
  }
}
function errorfun($e=未知错误！){
  $msg=<script language="javascript>javascript" type="text/javascript">;
  $msg.=alert(".$e.");;
  $msg.=history.back();;
  $msg.=</script>;
  echo $msg;
  exit;
}
}
?>

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