轉：c# Linq 的分頁[轉]

轉：http://www.cnblogs.com/leleroyn/archive/2008/05/14/1196811.html

不少學習Linq的朋友確定有本身所不一樣的方法，考慮這個問題我所想到的是

用Take(),Skip(),TakeWhile(),SkipUntil()中的方法來實現

首先看Take()是否可用

Take方法的做用是從結果中取固定數量的值，

MydbDataContext mydb=new MydbDataContext("server=.;database=mydb");

var query=from p in mydb.Products                orderby p.id descending                 select p;//取出Products中所用的項按降序排列 若是直接用take()

var q=query.take(n) 這樣只能取出前條n記錄，可是仍是讓咱們看到了分頁的曙光，仍是還有個skip嗎，skip能夠取出除去知足條件的剩下的記錄。若是咱們要把數據以每頁pagesize的數量來進行分頁，很簡單，很skip(pagersize*pagenum)而後在剩下的記錄中take(pagesize)不就獲得了想要的數據了麼。

 

varq=query.skip(pagesize*pagenum).take(pagesize) 就這麼簡單。

但願朋友們提供更好的方法來進行分頁，同時對這個方法的優劣性，進行批評指導 附上運行時生成的SQL(感謝：紫色陰影 、Boler Guo ） sql server2000： SELECT TOP 20 [t0].[CustomerID], [t0].[CompanyName], [t0].[ContactName], [t0].[ContactTitle], [t0].[Address], [t0].[City], [t0].[Region], [t0].[PostalCode], [t0].[Country], [t0].[Phone], [t0].[Fax] FROM [dbo].[Customers] AS [t0] WHERE NOT (EXISTS( SELECT NULL AS [EMPTY] FROM ( SELECT TOP 10 [t1].[CustomerID] FROM [dbo].[Customers] AS [t1] ) AS [t2] WHERE [t0].[CustomerID] = [t2].[CustomerID] )) sql server 2005 SELECT TOP 10 [t1].[CustomerID], [t1].[CompanyName], [t1].[ContactName], [t1].[ContactTitle], [t1].[Address], [t1].[City], [t1].[Region], [t1].[PostalCode], [t1].[Country], [t1].[Phone], [t1].[Fax] FROM ( SELECT ROW_NUMBER() OVER (ORDER BY [t0].[ContactName]) AS [ROW_NUMBER], [t0].[CustomerID], [t0].[CompanyName], [t0].[ContactName], [t0].[ContactTitle], [t0].[Address], [t0].[City], [t0].[Region], [t0].[PostalCode], [t0].[Country], [t0].[Phone], [t0].[Fax] FROM [dbo].[Customers] AS [t0] ) AS [t1] WHERE [t1].[ROW_NUMBER] > @p0 ORDER BY [t1].[ContactName] -- @p0: Input Int32 (Size = 0; Prec = 0; Scale = 0) [50] -- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build: 3.5.20XXX.X