我有一个简单的目标:通行证聚合函数作为参数
public class Machine
{
public string Name { get; set; }
public int Power { get; set; }
public int Type { get; set; }
}
再有就是持有这些对象的List类:
public class Aggregations
{
private List<Machine> _machines;
public Aggregations()
{
_machines = new List<Machine>
{
new Machine { Name = "XLR1", Power = 111, Type = 1 },
new Machine { Name = "XLR2", Power = 222, Type = 1 },
new Machine { Name = "XLR3", Power = 333, Type = 1 },
new Machine { Name = "XLR4", Power = 444, Type = 1 },
new Machine { Name = "XLR5", Power = 555, Type = 2 },
new Machine { Name = "XLR6", Power = 666, Type = 2 }
};
}
// ...
}
有是两个函数返回的机器列表具体标准如下:
public IEnumerable<Machine> MaxPower(IEnumerable<Machine> machines)
{
var maxPowerMachinesPerType = new List<Machine>();
var groups = machines.GroupBy(m => m.Type);
foreach (var g in groups)
{
var max = g.Max(m => m.Power);
var machine = g.First(m => m.Power == max);
maxPowerMachinesPerType.Add(machine);
}
return maxPowerMachinesPerType;
}
public IEnumerable<Machine> MinPower(IEnumerable<Machine> machines)
{
var minPowerMachinesPerType = new List<Machine>();
var groups = machines.GroupBy(m => m.Type);
foreach (var g in groups)
{
var min = g.Min(m => m.Power);
var machine = g.First(m => m.Power == min);
minPowerMachinesPerType.Add(machine);
}
return minPowerMachinesPerType;
}
}
正如您所看到的,两个函数几乎相等。只有“最大”和“最小”不同。
这些函数被称为是这样的:
IEnumerable<Machine> maxPowerMachines = MaxPower(_machines);
IEnumerable<Machine> minPowerMachines = MinPower(_machines);
因为我实际的程序稍微复杂一些,我虽然想调用其他聚合函数,我想通过聚合函数用作一个参数:(伪代码)
IEnumerable<Machine> maxPowerMachines = SuperFunction(_machines, m => m.Max);
IEnumerable<Machine> minPowerMachines = SuperFunction(_machines, m => m.Min);
IEnumerable<Machine> averagePowerMachines = SuperFunction(_machines, m => m.Average);
我希望你有意向。
正是我在找的东西。我尝试过这样的事情,但是缺少'g.Select(m => m.Power)'部分。谢谢! – RamNow