是否可以使用iComparer在对象中使用两个值对列表进行排序?
我有一个基于value1排序的自定义比较器类。但是,对value1和value2进行排序的最佳方法是什么?
按值2对列表进行排序,然后按值1工作吗?
答案 0 :(得分:12)
你的IComparer
课程应该处理它。例如:
public class ThingComparer : IComparer
{
public int Compare(object x, object y)
{
// null- and type-checking omitted for clarity
// sort by A, B, and then C
if (x.A != y.A) return x.A.CompareTo(y.A);
if (x.B != y.B) return x.B.CompareTo(y.B);
return x.C.CompareTo(y.C);
}
}
答案 1 :(得分:0)
如果您实施自己的比较器,您可以执行任何您想要的排序:
List<Customer> customers = GetCustomers();
customers.Sort(delegate(Customer x, Customer y)
{
if (x.Name != y.Name)
{
return x.Name.CompareTo(y.Name);
}
return x.Location.CompareTo(y.Location);
});
现在上面的代码不是IComparer类,但比较方法是相同的。
答案 2 :(得分:0)
public class ScratchComparer : IComparer<Scratch>
{
public int Compare(Scratch x, Scratch y)
{
return x.Foo.CompareTo(y.Foo).CompareTo(0.CompareTo(x.Bar.CompareTo(y.Bar)));
}
}
[TestFixture]
public class Scratch
{
public virtual int Foo { get; set; }
public virtual int Bar { get; set; }
[Test]
public void Should_sort()
{
var scratches = new[]
{
new Scratch {Foo = 1, Bar = 1},
new Scratch {Foo = 2, Bar = 1},
new Scratch {Foo = 1, Bar = 1},
new Scratch {Foo = 1, Bar = 2}
};
// IComparer
Array.Sort(scratches, new ScratchComparer());
scratches[0].Foo.ShouldEqual(1);
scratches[0].Bar.ShouldEqual(1);
scratches[1].Foo.ShouldEqual(1);
scratches[1].Bar.ShouldEqual(1);
scratches[2].Foo.ShouldEqual(1);
scratches[2].Bar.ShouldEqual(2);
scratches[3].Foo.ShouldEqual(2);
scratches[3].Bar.ShouldEqual(1);
// better
Scratch[] ordered = scratches.OrderBy(x => x.Foo).ThenBy(x => x.Bar).ToArray();
ordered[0].Foo.ShouldEqual(1);
ordered[0].Bar.ShouldEqual(1);
ordered[1].Foo.ShouldEqual(1);
ordered[1].Bar.ShouldEqual(1);
ordered[2].Foo.ShouldEqual(1);
ordered[2].Bar.ShouldEqual(2);
ordered[3].Foo.ShouldEqual(2);
ordered[3].Bar.ShouldEqual(1);
}
}