使用对象的HashSet检查相等性 [英] Checking equality with a HashSet of objects

问题描述

我正在尝试将两个Definition类型的哈希集与EqualityComparer<T>.Default.Equals(value, oldValue)进行比较. Definition定义如下

I am trying to compare two hashsets of Definition type as EqualityComparer<T>.Default.Equals(value, oldValue). Definition is defined as follows

public class Definition
{
    public string Variable { get; set; }
    public HashSet<Location> LocationList { get; set; }

    public override bool Equals(object obj)
    {
        Definition other = obj as Definition;
        return other.Variable.Equals(this.Variable) && other.LocationList!= null &&this.LocationList != null
            && other.LocationList.Count == this.LocationList.Count
            && other.LocationList == this.LocationList;
    }

    public override int GetHashCode()
    {
        return this.Variable.GetHashCode() ^ this.LocationList.Count.GetHashCode();// ^ this.LocationList.GetHashCode();
    }
}

public class Location
{
    public int Line { get; set; }
    public int Column { get; set; }
    public int Position { get; set; }
    public string CodeTab { get; set; }
    public Location(int line, int col, int pos, string tab)
    {
        Line = line;
        Column = col;
        Position = pos;
        CodeTab = tab;
    }
    public override bool Equals(object obj)
    {
        Location other = obj as Location;
        return this.CodeTab == other.CodeTab
            && this.Position == other.Position
            && this.Column == other.Column
            && this.Line == other.Line;
    }
    public override int GetHashCode()
    {
        return this.CodeTab.GetHashCode() ^ this.Position.GetHashCode() 
            ^ this.Column.GetHashCode() ^ this.Line.GetHashCode();
    }
}

对于类似的集合，尽管所有信息保持相同，但结果仍将以false的形式返回.唯一的区别是某些元素的位置可以互换，但是我知道HashSet在比较时不会保留或检查顺序.有人可以告诉我这里出了什么问题吗?

Somehow for a similar set, the result is returned as false despite all the information remaining the same. The only difference is that the position of some elements are interchanged, but I know that HashSet won't preserve or check the order while comparing. Can any one advise me on what is going wrong here?

PS:我也尝试取消注释this.LocationList.GetHashCode()，但是没有用.

PS: I tried uncommenting this.LocationList.GetHashCode() also, but didn't work.

推荐答案

您需要为集合创建一个比较器:

You need to create a comparer for the sets:

var setComparer = HashSet<Location>.CreateSetComparer();
return other.Variable.Equals(this.Variable) && setComparer.Equals(this.LocationList, other.LocationList);

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