[PHP知识库]php根据概率实现抽奖

//计算概率
function getRand($proArr) {
    $data = '';
    $proSum = array_sum($proArr); //概率数组的总概率精度 
    foreach ($proArr as $k => $v) { //概率数组循环
        $randNum = mt_rand(1, $proSum);
        if ($randNum <= $v) {
            $data = $k;
            break;
        } else {
            $proSum -= $v;
        }
    }
    unset($proArr);
    return $data;
}
//prize表示奖项内容，v表示中奖几率(若数组中七个奖项的v的总和为100，如果v的值为1，则代表中奖几率为1%，依此类推)
$jpdata = array(
    '0' => array('id' => 0, 'prize' => '谢谢参与', 'v' => 50),
    '1' => array('id' => 1, 'prize' => '苹果手机', 'v' => 1),
    '2' => array('id' => 2, 'prize' => '10元红包', 'v' => 5),
    '3' => array('id' => 3, 'prize' => '蓝牙耳机', 'v' => 5),
    '4' => array('id' => 4, 'prize' => '20元红包', 'v' => 5),
    '5' => array('id' => 5, 'prize' => '1元红包', 'v' => 20),
    '6' => array('id' => 6, 'prize' => '80元红包', 'v' => 4),
    '7' => array('id' => 7, 'prize' => '1000金币', 'v' => 10),
);

foreach ($jpdata as $key=>$value) {
    $arr[$value['id']] = $value['v'];

}
//根据概率获取奖项id 
$jp_id = getRand($arr);

可根据此算法在不断进行完善