class Program { static void Main(string[] args) { //Linq to Sql DataContext dc = new DataContext(new SqlConnection("server=.;database=SuperMarket;uid=sa;pwd=12345")); var ttt =from b in dc.GetTable<GoodsTypes>() group b by b.UpId into D11 select new { id = D11.Key, data = D11 }; foreach (var item in ttt) { Console.WriteLine("根据:"+item.id+"分组"); foreach (var item1 in item.data) { Console.WriteLine(" "+item1.TypeName); } } var resutldc = from b in dc.GetTable<GoodsTypes>() select b; foreach (var item in resutldc) { Console.WriteLine(item.TypeName); } dc.Dispose(); //Linq to Xml Book[] books = { new Book{Name="小白",Year=2006,Title="汇编语言"}, new Book{Name="小菜",Year=2006,Title="OOD"}, new Book{Name="小静",Year=2002,Title="你不知道的C#"}, }; //需求:查询2006年的书籍,并生成Xml var d = new XElement("Books", from b in books where b.Year == 2006 select new XElement("book", new XAttribute("Title", b.Title), new XElement("year", b.Year))); Console.WriteLine(d); //Linq To Objects string[] words = { "hello", "wonderful", "linq", "beautiful", "world" }; var result = from b in words orderby b ascending group b by b.Length into groups orderby groups.Key descending select new { lenth = groups.Key, data = groups }; foreach (var item in result) { Console.WriteLine("world length:" + item.lenth); foreach (var item1 in item.data) { Console.WriteLine(" " + item1); } } Console.Read(); } } [Table(Name = "GoodsTypes")] class GoodsTypes { [Column(IsPrimaryKey=true)] public int TypeId { get; set; } [Column(Name = "TypeName")] public string TypeName { get; set; } [Column] public string Memo { get; set; } [Column] public int UpId { get; set; } } class Book { public string Name { get; set; } public string Title { get; set; } public int Year { get; set; } }
Linq的简单应用_01
Hold on, everything is possible.