特定区域的最大和最小费率-lambda查询

Question

my table looks like-
  Area    MaxRate  MinRate Quarter year
    crossing  1000     800     1       2013
    crossing  900      700     2       2013
    crossing  800      600     3       2013

    crossing  700      500     4       2013
    crossing  600      500     1       2012
    crossing  550      450     2       2012
    crossing  500      400     3       2012

    crossing  450      350     4       2012
    indroper  2000     1500    1       2013
    indroper  1800     1500    2       2013


 I want max and min rates for the particular area in current year as -

 **Area    MaxRate  MinRate       year**
 crossing  1000     500           2013

请帮我在LINQ-lambda表示法

中查找查询

Answer 1

您可以使用GroupBy执行此操作：

var results = table.GroupBy(row => new { Area = row.Area, Year = row.year })
                   .Select(g => new { 
                                       Area = g.Key.Area, 
                                       MaxRate = g.Max(i => i.MaxRate),
                                       MinRate = g.Min(i => i.MinRate),
                                       Year = g.Key.Year
                                    });