数组乱序和根据权重抽取值

将数组随机排序

// 数组打乱排序
private T[] ShuffleArray(T[] currentArray)
{
    // 从数组的最后一个序号开始，依次往前设置各序号对应的值
    int maxIndex = currentArray.Length - 1;

    while (maxIndex > 0)
    {
        // 随机选得一个序号（已设置过值的序号不再参与抽取）
        int curIndex = Random.Range(0, maxIndex);
        // 当前选得的随机值
        T temp = currentArray[curIndex];
        // 将要设置值的序号的原值暂存起来
        currentArray[curIndex] = currentArray[maxIndex];
        // 设置当前目标序号的值为随机选得的值
        currentArray[maxIndex] = temp;

        maxIndex--;
    }

    return currentArray;
}

根据权重抽取值

// 根据权重获取值
// 字典的键为可选值，值为权重
private static T GetValueByWeights(Dictionary weightsDict)
{
    T targetValue = weightsDict.Keys.ToArray()[0];
    
    // 当前的随机值
    float currentRandomValue = Random.Range(0f, 1f);
    int totalWeight = 0;
    // 算出权重的总值作为分母
    foreach (var value in weightsDict.Values)
        totalWeight += value;

    float currentProbability = 0f;
    // 将权重转为概率进行计算
    foreach (var k in weightsDict.Keys)
    {
        currentProbability += ((float)weightsDict[k] / totalWeight);
        if (currentProbability >= currentRandomValue)
        {
            targetValue = k;
            break;
        }
    }

    return targetValue;
}