带有Linq的ArrayList，从个类类实例中查找最大值 [英] ArrayList with Linq, Find Maximum from custome class instance

问题描述

我有一个arraylist存储我的类的实例名为 PointOnLine



我的班级定义就像是

I am having a arraylist which stored instance of my class named PointOnLine

my class definition is like

public class PointOnLine
        {
            public float degree;
            public LinkedList.Node node;
            public int countPoint;
            public override string ToString()
            {
                return Convert.ToString(degree.ToString() + "        " + countPoint.ToString());
            }
        }

我正在添加大约100到500个实例数组列表中的类如上所述

I am adding approx 100 to 500 instances of above class in array list like this

arrayList.Add(objPointOnLine);
arrayList.Add(objPointOnLine1);
arrayList.Add(objPointOnLine2);

等等



现在我想找到 PointOnLine的实例具有 countPoint 字段的最大值，来自使用Linq或Limbda表达式的arraylist。





谢谢

and so on

Now I want to find instance of PointOnLine having maximum value of countPoint field, from arraylist using Linq or Limbda expression.


Thanks

推荐答案

var max_value = (from item in arrayList
               select item.countPoint).Max();

谷歌会更快地帮助你。

Google would have helped you faster.

为什么人们还在使用任何版本的.NET 2.0或更高版本的 ArrayList ？如果你使用 List< PointOnLine> ，那么之前的两个答案都可能有效。

Why on earth are people still using ArrayList for any version of .NET 2.0 or greater? If you use a List<PointOnLine> instead then both of the previous answers will probably work.

使用



arrayList.Max（a => a.countPoint）;



获取具有Maximum countPoint的对象。

Use

arrayList.Max(a => a.countPoint);

to get the object that have Maximum countPoint.

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