/// <summary>
/// 去除比例值为 0 的元素，并重新调整比例
/// </summary>
/// <param name="ratios"></param>
/// <returns></returns>
private List <AutoRatio> AdjustRatios(List <AutoRatio> ratios)
{
Decimal totalRatio, tmpRatio;
List <AutoRatio> tmpRatios;
totalRatio = 0;
tmpRatios = new List <AutoRatio>();
foreach (var r in ratios)
{
if (0 != r.percent)
{
tmpRatios.Add(r);
totalRatio += r.percent;
}
}
if (tmpRatios.Count == 0)
{
throw new Exception("未设置出题比例。");
}
else if ((Double)totalRatio < 0.5)
{
throw new Exception("出题比例小于 50% 。");
}
else if (totalRatio > 1)
{
throw new Exception("出题比例大于 100% 。");
}
tmpRatio = 0;
ratios = tmpRatios;
foreach (var r in ratios)
{
// 重新计算比例，且舍为较小的数
r.percent = StaticHelper.MathRound((Double)r.percent / (Double)totalRatio, 2);
tmpRatio += r.percent;
}
// 当调整后的百分比仍小于 1 时，将差值累加至最后一个元素
if (tmpRatio < 1)
{
ratios[ratios.Count - 1].percent += 1 - tmpRatio;
}
return(ratios);
}