代振軍同學的blog中描述了使用DataPager實現(xiàn)客戶端分頁：
http://www.cnblogs.com/daizhj/archive/2009/08/07/1529331.html
一般說來，在項目中一般很少使用這種客戶端的分頁方式，除非數(shù)據(jù)量很少（干脆不分頁算了）。
把大量的數(shù)據(jù)一次性傳輸?shù)娇蛻舳丝刹皇莻€明智的做法，我們一般都是從客戶端傳入查找條件參數(shù)（包括過濾條件和分頁條件參數(shù)），然后服務端從數(shù)據(jù)庫中找出符合查找條件的的記錄列表傳輸給客戶端，客戶端綁定到DataGrid控件上。
這里使用“開啟了Silverlight的WCF服務”來和客戶端（silverlight）程序進行通信，數(shù)據(jù)訪問采用Ado.net Entity Framework,解決方案結構如圖：

建立了一個測試用的數(shù)據(jù)庫：包含兩張表：

該實例除了演示了使用DataPager的服務器端分頁外還實現(xiàn)了使用Entity SQL的動態(tài)查找功能：

分頁控件很多人都寫過，但不像DataPager那樣要傳入個PagedCollectionView才行，一般傳入總記錄數(shù)和分頁大小就可以了，所以，我們給Datapager增加一個擴展方法來綁定總記錄數(shù)和分頁大小:

Code
public?static?class?DataPageExtension
????{
????????public?static?void?BindSource(this?DataPager?dataPager,?int?totalCount,?int?pageSize)
????????{
????????????List<int>?list?=?new?List<int>(totalCount);
????????????for?(int?i?=?0;?i?<?totalCount;?i++)?list.Add(i);
????????????PagedCollectionView?pcv?=?new?PagedCollectionView(list);
????????????pcv.PageSize?=?pageSize;
????????????dataPager.Source?=?pcv;
????????}
????}

WCF服務端的分頁方法如下：

Code
?[OperationContract]
????????public?List<MyEmployee>?GetEmployeeList(EmployeeFilter?filter,out?int?totalCount)
????????{
????????????using?(TestDBEntities?db?=?new?TestDBEntities())
????????????{
????????????????int?rowsCount?=?0;
????????????????StringBuilder?sbSql?=?new?StringBuilder("True?");
????????????????if?(filter.DeptID?!=?new?Guid())
????????????????????sbSql.Append(string.Format("and?it.Departments.DepartmentID?=?Guid'{0}'",?filter.DeptID));
????????????????sbSql.Append(string.Format("and?it.EmpolyeeName?like?'%{0}%'",?filter.EmpName));

????????????????var?query?=?from?emp?in?db.Employees.Where(sbSql.ToString())
????????????????????????????select?new?MyEmployee
????????????????????????????{
????????????????????????????????ID?=?emp.EmployeeID,
????????????????????????????????Name?=?emp.EmpolyeeName,
????????????????????????????????Sex?=?emp.EmployeeSex???"男"?:?"女",
????????????????????????????????Age?=?emp.EmployeeAge,
????????????????????????????????Address?=?emp.EmployeeAddress,
????????????????????????????????DeptName?=?emp.Departments.DepartmentName
????????????????????????????};
????????????????if?(filter.PageIndex?<=?0)
????????????????????rowsCount?=?query.Count();
????????????????totalCount?=?rowsCount;
????????????????query?=?query.OrderBy(t?=>?t.Name).Skip(filter.PageIndex?*?filter.PageSize).Take(filter.PageSize);
????????????????return?query.ToList();
????????????}
????????}

上面的代碼實現(xiàn)了使用Entity SQl的動態(tài)查找功能和分頁功能，可以看到：只有當pageindex 等于0的時候才計算總記錄數(shù)，提高了方法執(zhí)行的效率；方法的輸入?yún)?shù)和輸出參數(shù)都進行了實體類的封裝，建議在實際項目中也這樣做，特別是在使用依賴注入的時候。
在客戶端（Silverlight項目）中引用好服務后，頁面的cs代碼如下：

Code
using?System;
using?System.Collections.Generic;
using?System.Linq;
using?System.Net;
using?System.Windows;
using?System.Windows.Controls;
using?System.Windows.Documents;
using?System.Windows.Input;
using?System.Windows.Media;
using?System.Windows.Media.Animation;
using?System.Windows.Shapes;
using?System.Windows.Data;
using?DataPagerTest.EmployeeServiceReference;

namespace?DataPagerTest
{
????public?partial?class?MainPage?:?UserControl
????{
????????EmployeeServiceClient?client?=?new?EmployeeServiceClient();
????????EmployeeFilter?filter?=?new?EmployeeFilter();
????????public?MainPage()
????????{
????????????InitializeComponent();
????????}
????????private?void?UserControl_Loaded(object?sender,?RoutedEventArgs?e)
????????{
????????????dpEmployee.PageIndexChanged?+=?new?EventHandler<EventArgs>(dpEmployee_PageIndexChanged);
????????????cbDept.SelectionChanged?+=?new?SelectionChangedEventHandler(cbDept_SelectionChanged);
????????????BindCombox();
????????}

????????void?cbDept_SelectionChanged(object?sender,?SelectionChangedEventArgs?e)
????????{
????????????BindGrid(0);
????????}
????????void?dpEmployee_PageIndexChanged(object?sender,?EventArgs?e)
????????{
????????????BindGrid(dpEmployee.PageIndex);
????????}
????????private?void?btnQuery_Click(object?sender,?RoutedEventArgs?e)
????????{
????????????BindGrid(0);
????????}
????????private?void?BindGrid(int?pageIndex)
????????{
????????????Departments?dept?=?cbDept.SelectedItem?as?Departments;
????????????filter.DeptID?=?dept.DepartmentID;
????????????filter.EmpName?=?tbEmpName.Text.Trim();
????????????filter.PageIndex?=?pageIndex;
????????????filter.PageSize?=?9;
????????????client.GetEmployeeListCompleted?+=?new?EventHandler<GetEmployeeListCompletedEventArgs>(client_GetEmployeeListCompleted);
????????????client.GetEmployeeListAsync(filter);
????????}
????????void?client_GetEmployeeListCompleted(object?sender,?GetEmployeeListCompletedEventArgs?e)
????????{
????????????dgEmployee.ItemsSource?=?e.Result;
????????????if?(filter.PageIndex?<=?0)
????????????????dpEmployee.BindSource(e.totalCount,?filter.PageSize);
????????}
????????void?BindCombox()
????????{
????????????client.GetDepartmentListCompleted?+=?new?EventHandler<GetDepartmentListCompletedEventArgs>(client_GetDepartmentListCompleted);
????????????client.GetDepartmentListAsync();
????????}

????????void?client_GetDepartmentListCompleted(object?sender,?GetDepartmentListCompletedEventArgs?e)
????????{
????????????cbDept.ItemsSource?=?e.Result;
????????????cbDept.DisplayMemberPath?=?"DepartmentName";
????????????cbDept.SelectedIndex?=?0;
????????????BindGrid(0);
????????}

????????
????????
????}
}

在PageIndex等于0的時候調(diào)用BindSource擴展方法來綁定總記錄數(shù)和頁大小；里面還有個關于Combobox的數(shù)據(jù)綁定方法。這樣的分頁方法不知大家有何評價，歡迎拍磚。

?2009-08-18 更新：修改了數(shù)據(jù)庫的Departments表結構，實現(xiàn)了在Combobox里顯示TreeView的效果（如效果圖）。

總結

以上是生活随笔為你收集整理的使用Silverlight3中的DataPager实现服务器端分页的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯，歡迎將生活随笔推薦給好友。