c# - 如何获得每个月的总和？

Question

A 有一个包含 9 月、10 月、11 月的收藏列表，但是我想特别添加每个月

Start Time                    EndTime
September 11,2016 5:00PM   September 11,2016 8:00PM  
September 12,2016 10:00AM  September 12,2016 8:00PM 
October 1,2016 5:00PM      September 11,2016 8:00PM  
October 2,2016 10:00AM     September 12,2016 8:00PM 
November 1,2016 5:00PM     November 11,2016 8:00PM  
November 2,2016 10:00AM    November 12,2016 8:00PM 

我的代码

List<MonthHours> oList=new List<MonthHours>();
Int total=0;
TimeSpan span=new TimeSpan();
foreach(var data in oList)
{
Span=data.EndTime-data.StartTime;
Total+=span.hours;
}

我得到了从 9 月到 11 月的所有总和，我真正想要的是按月示例获得总和在 9 月我有 3 小时，int 10 月 5 小时，11 月 5 小时。

抱歉新手TIA

Answer 1

var result = oList
    .GroupBy(data => data.StartTime.ToString("MMMM"))
    .Select(g => new MonthHours {
        Month = g.Key,
        Total_Hours = g.Sum(d => (d.EndTime - d.StartTime).TotalHours)
    });

foreach (var month in result) {
    var str = string.Format("Month : {0}, Total Hours : {1}", month.Month, month.Total_Hours);
}