转:http://www.16kan.com/article/detail/318657.html
Introduction介绍
In this article we will explore the classSPListItemCollectionPosition
and its advantages.在这篇文章中,我们将探讨的的类SPListItemCollectionPosition
和它的优点。
This is a server object model type and should be used along with modules executed on the server.这是一个服务器对象模型的类型,应该在服务器上执行的模块一起使用。
What is SPListItemCollectionPosition?什么是SPListItemCollectionPosition?
This class enables Pagination for Lists inside SharePoint.这个类可以在SharePoint中的列表分页。
It stores the state of a page and thus helps in fetching the next page in the dataset.它存储的页面状态,从而有助于在获取下一个页面中的数据集。
The class can be used along with theSPQuery
object.类可以一起使用SPQuery
对象。
What are the advantages of SPListItemCollectionPosition?什么是的优势SPListItemCollectionPosition?
It provides the following advantages:它提供了以下优点:
- Reduced network traffic减少网络流量
- Reduced memory减少内存
- Faster result delivery提供更快的结果
Going practical走向实用
Now we can try ourselves the usage ofSPListItemCollectionPosition
.现在,我们可以尝试自己的使用SPListItemCollectionPosition
。
Here we are going to create 1000 list items and fetch 10 at a time.在这里,我们要创建1000个列表项,并一次获取10个。
The web part associated will be containing page navigation buttons.该网站的部分将被包含页导航按钮。
Step 1 : Create a Visual WebPart solution.
步骤1:创建一个Visual Web部件解决方案。
Create a new Visual WebPart solution and give it a meaningful name.创建一个新的Visual Web部件解决方案,并给它起一个有意义的名字。
Step 2 : Place controls:
步骤2:将控制:
Place the following controls for the WebPart.将以下控件的WebPart。
Step 3 : Create the Data
第3步 :创建数据
Now we need to create a list with 1000 items.现在,我们需要创建一个列表,有1000个项目。
The following code does the purpose.下面的代码的目的。
Place the code inside the Created Data button click event.将里面的代码创建的数据按钮的Click事件。
protected void CreateDataButton_Click( object sender, EventArgs e) 保护的无效 CreateDataButton_Click( 对象发件人,EventArgs五)
{ {
using (SPWeb web = SPContext.Current.Web) (使用SPWeb网站,= SPContext.Current.Web,)
{ {
string listName = " Contacts 1000" ; 串 联系导航首页=“1000”;
SPList list = null ; SPList列表= NULL; // Create Lists / /创建列表
try 尝试
{ {
list = web.Lists[listName]; = web.Lists [名];
} }
catch 抓
{ {
web.Lists.Add(listName, " A Contact List of 1000 items" , SPListTemplateType.Contacts); web.Lists.Add(导航首页,“1000项目”,SPListTemplateType.Contacts的联系人名单 );
list = web.Lists[listName]; = web.Lists [名]; // Create Data / /创建数据
for ( int i = 1 ; i <= 1000 ; i++) (i = 1; <= 1000;我+ +)
{ {
SPListItem item = list.Items.Add(); SPListItem的项目= list.Items.Add();
item[ " First Name" ] = " First Name " + i.ToString();项目[“名字”] =“姓”+ i.ToString();
item[ " Last Name" ] = " Last Name " + i.ToString();项目“姓”] =“姓”+ i.ToString(); item.Update(); item.Update();
} }
} }
} }
} }
Now we can try creating the data by executing the above code.现在,我们可以尝试创建的数据执行上面的代码。
The steps are:步骤如下:
- Build the solution构建解决方案
- Deploy the solution部署解决方案
- Insert WebPart into Page将Web部件到页面
- Click the Create Data button单击“创建数据”按钮
You can see that inside the Lists link, a new list named
Contacts 1000 is created with the following data.你可以看到,里面的列表链接,一个新的列表,
名为 Contacts 1000创建以下数据。
Step 4 : Show the Data
第4步 :显示数据
Now we are ready to show the first 10 list items.现在,我们已经准备好显示前10个列表项。
Here we are showing only 10 items per page and saving the Page information in the View State of the User Control.在这里,我们只有10个项目每页显示的页面信息保存在视图状态中的用户控件。
protected void ShowDataButton_Click( object sender, EventArgs e) 保护的无效 ShowDataButton_Click( 对象发件人,EventArgs五)
{ {
SPQuery query = new SPQuery(); SPQuery查询= 新 SPQuery();
query.RowLimit = 10 ; query.RowLimit = 10;
query.ViewFields = " <FieldRef Name=\"Title\" />" + /* Title is LastName column */ query.ViewFields =“<FieldRef Name=\"Title\" />”+ / *标题是LastName列* /
" <FieldRef Name=\"FirstName\" Nullable=\"TRUE\" Type=\"Text\"/>" ; “<FieldRef Name=\"FirstName\" Nullable=\"TRUE\" Type=\"Text\"/>”;
string listName = " Contacts 1000" ; 串 联系导航首页=“1000”;
SPList list = SPContext.Current.Web.Lists[listName]; SPList SPContext.Current.Web.Lists [名]; SPListItemCollection collection = list.GetItems(query);的SPListItemCollection收集list.GetItems(查询); PagingInfo.SavePageInfo(ViewState, collection.ListItemCollectionPosition.PagingInfo); PagingInfo.SavePageInfo(ViewState中collection.ListItemCollectionPosition.PagingInfo); GridView1.DataSource = collection.GetDataTable(); GridView1.DataSource:= collection.GetDataTable();
GridView1.DataBind(); GridView1.DataBind();
} }
Note : Here we are using theSPListItemCollection
object to memorize the items fetched.
注 :在这里,我们使用的是记忆的项目获取SPListItemCollection
对象。 To persist this information between page requests, we are saving it to the ViewState using thePagingInfo
class.要坚持这个页面请求之间的信息,我们保存它的ViewState使用PagingInfo
类的了。
You can execute the code and see the results as below:您可以执行的代码,看看结果如下:
Note : In this case, the ViewState contains the following data:
Paged=TRUE&p_ID=10. It stores the last ID of the item displayed.
注 :在这种情况下,ViewState中包含以下数据: 分页= TRUE&P_ID = 10,它存储的最后一个ID显示的项目。
This ID is required for processing the next button.这个ID是需要处理“下一步”按钮。
Step 5 : Next page functionality
第5步 :接下来的页面功能
Following is the code for the Next Page button functionality.以下是代码的下一页“按钮的功能。
protected void NextPageButton_Click( object sender, EventArgs e) 保护的无效 NextPageButton_Click( 对象发件人,EventArgs五)
{ {
SPQuery query = new SPQuery(); SPQuery查询= 新 SPQuery();
query.RowLimit = 5 ; query.RowLimit = 5;
query.ViewFields = " <FieldRef Name=\"Title\" />" + /* Title is LastName column */ query.ViewFields =“<FieldRef Name=\"Title\" />”+ / *标题是LastName列* /
" <FieldRef Name=\"FirstName\" Nullable=\"TRUE\" Type=\"Text\"/>" ; “<FieldRef Name=\"FirstName\" Nullable=\"TRUE\" Type=\"Text\"/>”;
string listName = " Contacts 1000" ; 串 联系导航首页=“1000”;
SPList list = SPContext.Current.Web.Lists[listName]; SPList SPContext.Current.Web.Lists [名]; /* New */ / *新* /
query.ListItemCollectionPosition = PagingInfo.GetNextPagePosition(ViewState); query.ListItemCollectionPosition PagingInfo.GetNextPagePosition(ViewState)的; SPListItemCollection collection = list.GetItems(query);的SPListItemCollection收集list.GetItems(查询); PagingInfo.SavePageInfo(ViewState, collection.ListItemCollectionPosition.PagingInfo); PagingInfo.SavePageInfo(ViewState中collection.ListItemCollectionPosition.PagingInfo); GridView1.DataSource = collection.GetDataTable(); GridView1.DataSource:= collection.GetDataTable();
GridView1.DataBind(); GridView1.DataBind();
} }
The code takes the Page Position from the View State using thePagingInfo
class.从视图状态使用PagingInfo
类的代码需要的页面位置。
You can see the following results on executing and clicking the Next button.你可以看到下面的结果上执行,然后单击“下一步”按钮。
So this concludes our experiment with theSPListItemCollectionPosition
class.因此,总结我们的实验的SPListItemCollectionPosition
类。
About the Utility class关于实用工具类
Following is the body of thePagingInfo
class.以下是人体的PagingInfo
类。
It is a static class basically doing theSavePageInfo()
and GetNextPagePosition()
functionalities by saving the Page Info string to the View State and getting back.它是一个静态类,基本上是做SavePageInfo()
和GetNextPagePosition()
功能页面信息字符串保存的视图状态和回。
public static class PagingInfo 公共静态类 PagingInfo的
{ {
public static void SavePageInfo(StateBag viewState, string pagingInfo) 公共静态无效 SavePageInfo的(StateBag的ViewState的, 串 pagingInfo;)
{ {
viewState[ " PagingInfo" ] = pagingInfo; ViewState的“PagingInfo”] = pagingInfo;
} } public static SPListItemCollectionPosition GetNextPagePosition(StateBag viewState) 的公共静态 SPListItemCollectionPosition GetNextPagePosition(StateBag的ViewState的)
{ {
string pagingInfo = string .Empty; 串 pagingInfo = 字符串 。空; if (viewState[ " PagingInfo" ] != null ) (ViewState的“PagingInfo”]!= NULL)
pagingInfo = viewState[ " PagingInfo" ].ToString(); pagingInfo = ViewState的[“PagingInfo”]。的ToString(); return new SPListItemCollectionPosition(pagingInfo); 返回新 SPListItemCollectionPosition的(pagingInfo);
} }
} }
This concludes the usage of theSPListItemCollectionPosition
class.就此结束使用的SPListItemCollectionPosition
类。
About the Previous Page functionality关于上一页功能
As theSPListItemCollectionPosition
is meant for providing paginated results for the next page by storing the ID value of the last item in the page, to perform the functionality of Previous page, we need to work more on getting the ID of the first item
in the page.的SPListItemCollectionPosition
提供存储的ID值在页面中的最后一个项目,执行功能的前一页,下一个页面分页结果是,我们需要更多的工作在页面上获得的第一个项目的ID 。
I have added some links that should give an idea of enabling the Previous functionality.我增加了一些的链接应该给一个想法,让以前的功能。
References参考文献
-
MSDN
Information MSDN信息 -
Previous
Page Functionality 上一页功能 -
Paging
with SPListItemCollectionPosition 寻呼SPListItemCollectionPosition
Summary总结
In this article we have explored the advantages and use ofSPListItemCollectionPosition
.在这篇文章中,我们探讨的优势和使用SPListItemCollectionPosition
。
In real world scenarios, this class provides faster results with reduced network traffic involved.在真实世界的情景,减少网络流量的参与,这个类提供了更快的结果。
The attachment contains the source code we discussed.附件包含源代码,我们讨论。
You can download and install it to your SharePoint site for testing.您可以下载并安装到您的SharePoint网站进行测试。