随机抽取算法

    /// <summary>
    /// 随机抽取
    /// </summary>
    /// <param name="dataList">直接传输每种类型的个数的List，比如0号50个，1号10个，2号20个</param>
　　 /// 示例：  List<int> _list = new List<int> {50,10,20};
    /// <returns>最终返回为抽取到了哪个编号</returns>
    public static int RandomGetIndex(List<int> dataList)
    {
        int maxNum = 0;
        foreach (var one in dataList)
        {
            maxNum += one;
        }
        //int randomNum = RandomHelper.RandomNumber(0, maxNum);
        int randomNum = UnityEngine.Random.Range(0, maxNum);
        int weightNum = 0;
        for (int i = 0; i < dataList.Count; i++)
        {
            weightNum += dataList[i];
            if (randomNum < weightNum)
            {
                return i;
            }
        }
        return 0;
    }