通过求和几行对列表进行排序
本文关键字:列表 排序 几行 求和 | 更新日期: 2023-09-27 18:25:50
我有这样的类:
public class UserDataPoint
{
public string User { get; set; }
public string Category { get; set; }
public int Spend { get; set; }
public UserDataPoint(string strUser, string strCategory, int intSpend)
{
User = strUser;
Category = strCategory;
Spend = intSpend;
}
}
其中填充了这样的数据:
var myList = new List<UserDataPoint>() {
new UserDataPoint("Bob", "Local", 34),
new UserDataPoint("Bob", "National", 16),
new UserDataPoint("Bob", "Mobile", 7),
new UserDataPoint("John", "Local", 18),
new UserDataPoint("Fred", "National", 22),
new UserDataPoint("Fred", "International", 65) };
我想填充一个数组:
UserDataPoint[] myArray;
使用myList中的数据,但按"用户"排序,"支出"总额最高。因此,从上面的示例数据来看,Fred将是列表中的第一位(22+65=87),其次是Bob(34+16+7=57),最后是John(18)。
因此,我得到的数组将按以下顺序填充:
UserDataPoint[] myArray = new UserDataPoint[] {
new UserDataPoint("Fred", "National", 22),
new UserDataPoint("Fred", "International", 65),
new UserDataPoint("Bob", "Local", 34),
new UserDataPoint("Bob", "National", 16),
new UserDataPoint("Bob", "Mobile", 7),
new UserDataPoint("John", "Local", 18) };
如何实现LINQ语句来对myList执行此排序,从而获得myArray?
非常感谢任何能提供帮助的人。
UserDataPoint[] myArray =
myList.GroupBy(udp => udp.User)
.OrderByDescending(g => g.Sum(udp => udp.Spend))
.SelectMany(g => g)
.ToArray();