C＃按列表项按组排序

Question

我有一个列表，其中包含一些BW具有2个 属性的对象，分别为shape和quantity。

根据preShape值和preQuantity给定的值，我将使用和将每个项目排序。所述优先级为第一，则是第二优先级。我已经对和进行了排序，然后对进行了排序，并取决于和。这样的结果很好：List<BW>preShapepreQuantityshapequantityList<BW>GroupByshapequantitypreShapepreQuantity

• “预成形”值：MN22
• “量化前”值：20

 

| shape | quantity|
--------|----------
| MN22  | 20      |
| MN22  | 14      |
| MN11  | 20      |
| MN11  | 10      |
| ANT   | 20      |
| ANT   | 18      |
| ANT   | 16      |
| ANT   | 10      |

但我想这样List<BW>：

| shape | quantity|
--------|----------
| MN22 | 20       |
| MN22 | 14       |
| MN11 | 10       |
| MN11 | 20       |
| ANT  | 20       |
| ANT  | 10       |
| ANT  | 16       |
| ANT  | 18       |

我尝试使用for循环和swap函数进行排序，但结果与我想要的结果不同。

我想按列表排序，结果类似于第二张表。

我需要组形状，使他们在一组，我会比较形状在列表中的每个项目与预形状，如果他们匹配，我将排序列表与形预则数量将是第二个条件。但是，组A中最后一项的数量后必须跟相同数量的组B中的第一项。如果它们不匹配，则组B中第一项的数量将按ASC排序。

我在此处附加我的代码以获取更多描述 我的dottnetfiddle代码

public static void Main()
{
    List<BW> lst = new List<BW>(){
        new BW(){ shape = "MN11", quantity = 20},
        new BW(){ shape = "MN11", quantity = 10},
        new BW(){ shape = "MN22", quantity = 14},
        new BW(){ shape = "MN22", quantity = 20},
        new BW(){ shape = "ANT", quantity = 16},
        new BW(){ shape = "ANT", quantity = 18},
        new BW(){ shape = "ANT", quantity = 20},
        new BW(){ shape = "ANT", quantity = 10}

    };
    string preShape = "MN22";
    int preQuantity = 20;

    var tempList = lst.GroupBy(c=>c.shape).Select(g=> new {shapeGroup = g.Key, BW = g.OrderBy(c=> c.shape.Equals(preShape)).ThenByDescending(c=>c.quantity)}).OrderByDescending(g=>g.shapeGroup.Equals(preShape));
    //var tempList = lst.GroupBy(c=>c.shape).Select(g=> new {shapeGroup = g.Key, BW = g.OrderByDescending(c => c.shape.Equals(preShape))}).OrderBy(g=>g.BW.First().quantity == preQuantity);;

    foreach (var shape in tempList)
    {
        var lastGroupBW_Item = shape.BW.LastOrDefault();
        //Console.WriteLine("{0}", shape.shape);
        foreach (var bw in shape.BW)
        {
            if(shape.BW.ToList().IndexOf(bw) > 0 )
            {
                shape.BW.OrderBy(c=>c.quantity == lastGroupBW_Item.quantity).ThenBy(c=>c.quantity);
            }
            Console.WriteLine("{0}|{1}", bw.shape,bw.quantity);
        }
    }

}

我想要的最后一个结果就像上面描述的第二张表。提前致谢！

Answer 1

因此，的项目shape == preShape应位于顶部和顶部quantity == preQuantity；您可以bool为此排序（请注意false < true）：

 List<BW> lst = ...

 var result = lst
   .OrderByDescending(item => item.shape != preShape)       // preShape on the top  
   .ThenByDescending(item => item.shape)                    // in case of tie by shape
   .ThenByDescending(item => item.quantity != preQuantity)  // preQuantity on the top
   .ThenBy(item => item.quantity);                          // in case of tie by quantity

演示：（我Tuple为了模拟而使用BW）

  List<(string shape, int quantity)> lst = new List<(string shape, int quantity)>(){
    ( shape :"MN11", quantity : 20),
    ( shape :"MN11", quantity : 10),
    ( shape :"MN22", quantity : 14),
    ( shape :"MN22", quantity : 20),
    ( shape : "ANT", quantity : 16),
    ( shape : "ANT", quantity : 18),
    ( shape : "ANT", quantity : 20),
    ( shape : "ANT", quantity : 10),
  };

  string preShape = "MN22";
  int preQuantity = 20;

  var result = lst
   .OrderByDescending(item => item.shape == preShape)       // preShape on the top  
   .ThenByDescending(item => item.shape)                    // in case of tie by shape
   .ThenByDescending(item => item.quantity == preQuantity)  // preQuantity on the top
   .ThenBy(item => item.quantity);                          // in case of tie by quantity

  Console.Write(string.Join(Environment.NewLine, result));

结果：

(MN22, 20) // preShape is the first to come; preQuantity is on the top within MN22 shape
(MN22, 14)
(MN11, 20) // preQuantity is on the top within the MIN11 shape
(MN11, 10)
(ANT, 20)  // preQuantity is on the top within the ANT shape
(ANT, 10)
(ANT, 16)
(ANT, 18)