设置概率抽奖 js

// 奖品数组，每个奖品包含名称和对应的中奖概率
const prizes = [
    { name: '一等奖', probability: 0.1 },
    { name: '二等奖', probability: 0.2 },
    { name: '三等奖', probability: 0.3 },
    { name: '谢谢参与', probability: 0.4 }
];

function getRandomPrize(prizes) {
    // 计算所有奖品概率的总和
    const totalProbability = prizes.reduce((sum, prize) => sum + prize.probability, 0);
    // 生成一个 0 到总概率之间的随机数
    const random = Math.random() * totalProbability;
    let cumulativeProbability = 0;
    for (const prize of prizes) {
        cumulativeProbability += prize.probability;
        if (random < cumulativeProbability) {
            return prize.name;
        }
    }
}

// 测试抽奖函数
for (let i = 0; i < 10; i++) {
    console.log(getRandomPrize(prizes));
}