/// <summary>
/// 获取指定年月的当月工作日，不支持国家法定节假日的判断和计算，只计算周六和周日为非工作日
/// </summary>
/// <param name="year">年份</param>
/// <param name="month">月份</param>
/// <returns>返回指定月份的当月工作日天数</returns>
public int GetWorkingDays(int year,int month) 
{
    //获取该月的第一天
    DateTime dateTime = Convert.ToDateTime(DateTime.Now.ToString("yyyy-MM-01"));
    //获取该月总计天数
    int days = DateTime.DaysInMonth(year,month);
    //休息天数
    int weekDays = 0;
    for (int i = 0; i < days; i++)
    {
        //每逢周六/周日 休息天数增加一天
        switch (dateTime.DayOfWeek)
        {
            case DayOfWeek.Sunday:
                weekDays++;
                break;
            case DayOfWeek.Saturday:
                weekDays ++;
                break;
            default:
                break;
       }
       dateTime.AddDays(1);
    }
    //工作日等于当月总天数减去非工作日
    int workDays = days - weekDays;
    return workDays;
}