function get_gift(){ 
  //拼裝獎項數組 
  // 獎項id，獎品，概率
  $prize_arr = array( 
   '0' => array('id'=>1,'prize'=>'平板電腦','v'=>0), 
   '1' => array('id'=>2,'prize'=>'數碼相機','v'=>0), 
   '2' => array('id'=>3,'prize'=>'音箱設備','v'=>0), 
   '3' => array('id'=>4,'prize'=>'4G優盤','v'=>5), 
   '4' => array('id'=>5,'prize'=>'10Q幣','v'=>0), 
   '5' => array('id'=>6,'prize'=>'空獎','v'=>5), 
  ); 
  foreach ($prize_arr as $key => $val) { 
   $arr[$val['id']] = $val['v'];//概率數組 
  } 
  $rid = $this->get_rand($arr); //根據概率獲取獎項id 
  $res['yes'] = $prize_arr[$rid-1]['prize']; //中獎項 
  unset($prize_arr[$rid-1]); //將中獎項從數組中剔除，剩下未中獎項 
  shuffle($prize_arr); //打亂數組順序 
  for($i=0;$icount($prize_arr);$i++){ 
   $pr[] = $prize_arr[$i]['prize']; //未中獎項數組 
  } 
  $res['no'] = $pr; 
  // var_dump($res);

   
  if($res['yes']!='空獎'){ 
   $result['status']=1; 
   $result['name']=$res['yes']; 
  }else{ 
   $result['status']=-1; 
   $result['msg']=$res['yes']; 
  } 
  //return $result; 
  var_dump($result);
 } 

 //計算中獎概率
 function get_rand($proArr) { 
  $result = ''; 
  //概率數組的總概率精度 
  $proSum = array_sum($proArr); 
  // var_dump($proSum);
  //概率數組循環 
  foreach ($proArr as $key => $proCur) { 
  $randNum = mt_rand(1, $proSum); //返回隨機整數 

  if ($randNum = $proCur) { 
   $result = $key; 
   break; 
  } else { 
   $proSum -= $proCur; 
  } 
  } 
  unset ($proArr); 
  return $result; 
 }