Linq应用记录一【将同事好多行代码改造成Linq方式】

同事代码：

 

        public static List<SimpleSoft> GetOrderedSofts(List<SimpleSoft> softs)
        {
            List<SimpleSoft> orderSofts = new List<SimpleSoft>();
            var softsEnum = from a in softs
                            orderby a.f_identifier ascending
                            select a;
            foreach (var soft in softsEnum)
            {
                if (orderSofts.Count > 0)
                {
                    SimpleSoft simpleSoft = orderSofts[orderSofts.Count - 1];
                    if (soft.f_identifier != simpleSoft.f_identifier)
                    {
                        orderSofts.Add(soft);
                    }
                    else
                    {
                        try
                        {
                            Version v1 = new Version(simpleSoft.f_version);
                            Version v2 = new Version(soft.f_version);
                            if (v2.CompareTo(v1) > 0)
                            {
                                orderSofts[orderSofts.Count - 1] = soft;
                            }
                        }
                        catch
                        {
                            if (soft.f_version.CompareTo(simpleSoft.f_version) > 0)
                            {
                                orderSofts[orderSofts.Count - 1] = soft;
                            }
                        }
                    }
                }
                else
                {
                    orderSofts.Add(soft);
                }
            }
            return orderSofts;
        }

 

 

Linq改造后的代码：

 

        public static List<SimpleSoft> GetOrderedSofts(List<SimpleSoft> softs)
        {
            List<SimpleSoft> orderSofts = new List<SimpleSoft>();
            var softsGroup = from x in softs group x by x.f_identifier into y select y;
            foreach (var group in softsGroup)
            { 
                var softsOrder = group.OrderByDescending(ver=>ver.f_version).Take(1);
                foreach (var soft in softsOrder)
                {
                    orderSofts.Add(soft);
                }
            }
            return orderSofts;
        }

 

 

以此做一个简单的记录，方便回顾 。。。

 

 

今天又改进了一下代码， 一句话搞定 。。。。

 

from x in Items group x by x.ProductId into y select new {grouping=(from g in y orderby g.ListPrice select g).Take(1)}