PHP+AJAX实现的幸运大转盘抽奖实例，通过奖品库存、中奖次数来计算中奖概率
奖品设置
$prizes = array(
0 => array(
“id” => 0, //中奖id
“name” => “谢谢参与”, //奖品名称
“count” => “100”, //库存
),
1 => array(
“id” => 1,
“name” => “罗浮山门票”,
“count” => “40”,
),
2 => array(
“id” => 2,
“name” => “罗浮山嘉宝田温泉体验券”,
“count” => “40”,
),
3 => array(
“id” => 3,
“name” => “精美旅游书籍《山水酿惠州》”,
“count” => “40”,
),
4 => array(
“id” => 4,
“name” => “碧海湾漂流门票”,
“count” => “40”,
),
5 => array(
“id” => 5,
“name” => “南昆山门票”,
“count” => “40”,
),
6 => array(
“id” => 6,
“name” => “云顶温泉精美礼品”,
“count” => “40”,
),
);
获取中奖概率，若是库存为0的则不计算
function getRand($proArr, $proCount) {
$result = ‘’;
$proSum = 0;
foreach ($proCount as $key => $val) {
if ($val <= 0) {
continue;
} else {
$proSum = $proSum + $proArr[$key];
}
}
foreach ($proArr as $key => $proCur) {
if ($proCount[$key] <= 0) {
continue;
} else {
$randNum = mt_rand(1, $proSum);
if ($randNum <= $proCur) {
$result = $key;
break;
} else {
$proSum -= $proCur;
}
}
}
unset($proArr);
return $result;
}
