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Linq查询到orderby级别然后是父项和子项

[英]Linq query to orderby level then parent and child item

我查了一些有序的例子,但我仍然对最好的linq表达式感到困惑,要在代码中对程序集进行排序以生成这个列表:

Level Parent      Child  
1     L010057501U 231-100-002  
1     L010057501U 307-355-022  
2     307-355-022 307-355-058  
3     307-355-058 355-100-008  
3     307-355-058 357-200-002  
2     307-355-022 307-355-059  
3     307-355-059 355-200-005  
3     307-355-059 357-100-002  

结果需要按级别排序,但子项需要紧跟在父级之后才能列出下一个父级。 装配的组件可以是几层深。 我希望我已经充分解释了。

    class Program
{
    static void Main(string[] args)
    {
        SortAssembly();
        Console.ReadLine();
    }
    class Assembly
    {
        public int Level { get; set; }
        public string Parent { get; set; }
        public string Component { get; set; }
    }

    private static void SortAssembly()
    {
        Assembly[] assemblies = { 
            new Assembly { Level=1, Parent="L010057501U", Component="231-100-002" },
            new Assembly { Level=1, Parent="L010057501U", Component="307-355-022" },
            new Assembly { Level=2, Parent="307-355-022", Component="307-355-058" },
            new Assembly { Level=2, Parent="307-355-022", Component="307-355-059" },
            new Assembly { Level=3, Parent="307-355-058", Component="355-100-008" },
            new Assembly { Level=3, Parent="307-355-059", Component="355-200-005" },
            new Assembly { Level=3, Parent="307-355-059", Component="357-100-002" },
            new Assembly { Level=3, Parent="307-355-058", Component="357-200-002" }
        };

        var query = ???  

        foreach (var part in query)
        {
            Console.WriteLine("{0} - {1} - {2}", part.Level, part.Parent, part.Component);
        }
    }
}

1 - L010057501U - 231-100-002
1 - L010057501U - 307-355-022
____2 - 307-355-022 - 307-355-058
________3 - 307-355-058 - 355-100-008
________3 - 307-355-058 - 357-200-002
____2 - 307-355-022 - 307-355-059
________3 - 307-355-059 - 355-200-005
________3 - 307-355-059 - 357-100-002

我试图实现IComparable但我没有抓住它。 仍然需要帮助。

你可以试试以下

using System;
using System.Linq;


    public class Assembly
    {
        public int Level { get; set; }
        public string Parent { get; set; }
        public string Component { get; set; }
        public bool Visited{get;set;} // to track visited levels
    }
public class Program
{
    public static void Main()
    {
                Assembly[] assemblies = { 
            new Assembly { Level=1, Parent="L010057501U", Component="231-100-002" },
            new Assembly { Level=1, Parent="L010057501U", Component="307-355-022" },
            new Assembly { Level=2, Parent="307-355-022", Component="307-355-058" },
            new Assembly { Level=2, Parent="307-355-022", Component="307-355-059" },
            new Assembly { Level=3, Parent="307-355-058", Component="355-100-008" },
            new Assembly { Level=3, Parent="307-355-059", Component="355-200-005" },
            new Assembly { Level=3, Parent="307-355-059", Component="357-100-002" },
            new Assembly { Level=3, Parent="307-355-058", Component="357-200-002" }
        };
        DisplayAssemblies(assemblies);

    }

    private static void DisplayAssemblies(Assembly[] data)
    {
        // order the data to be sorted by levels
        var levels=data.OrderBy(t=>t.Level);
        foreach(var level in levels)
            if(!level.Visited)
                DisplayLevel(level,data);

    }

    private static void DisplayLevel(Assembly level, Assembly[] data)
    {
        var childs=data.Where(t=>t.Parent==level.Component).ToArray();
        Console.WriteLine("{0} - {1} - {2}", level.Level, level.Parent, level.Component);
        level.Visited=true;
        foreach(var child in childs)
        {       
            DisplayLevel(child,data);
        }
    }
}

OUTPUT:


1 - L010057501U - 231-100-002
1 - L010057501U - 307-355-022
2 - 307-355-022 - 307-355-058
3 - 307-355-058 - 355-100-008
3 - 307-355-058 - 357-200-002
2 - 307-355-022 - 307-355-059
3 - 307-355-059 - 355-200-005
3 - 307-355-059 - 357-100-002

这是一个现场演示

希望这个能对您有所帮助

让您的Assembly类实现IComparable ,它允许您通过实现其唯一的方法来定义它们的排序方式: CompareTo()

我认为你说你需要先按Level,然后是Parent,然后是Component。 如果是这样,你可以使用这样的东西:

class Assembly:IComparable
{
    public int Level { get; set; }
    public string Parent { get; set; }
    public string Component { get; set; }

    public int CompareTo(object obj)
    {
        var other = obj as Assembly;

        if (this.Level != other.Level)
        {
            return this.Level.CompareTo(other.Level);
        }

        if (this.Parent != other.Parent)
        {
            return this.Parent.CompareTo(other.Parent);
        }

        return this.Component.CompareTo(other.Component);
    }
}

但是,如果我误解你的逻辑,那么这个想法是具有CompareTo()返回一个正整数,如果this到来之前other若是否定整数other来之前, this (或0 ,如果他们是同等级别的)。

一旦实施了IComparable您就可以:

query = assemblies.OrderBy(a => a);

为了按照自己的自定义顺序对Assemly对象进行排序

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