ContentIterator 类

提供方法来循环访问项列表、 列表、 网站来控制传输的数据量 （即，以避免引发SPQueryThrottledException)。

继承层次结构

System.Object
  Microsoft.Office.Server.Utilities.ContentIterator
    Microsoft.Office.Server.Utilities.TimerJobUtility

命名空间：  Microsoft.Office.Server.Utilities
程序集：  Microsoft.Office.Server（位于 Microsoft.Office.Server.dll 中）

语法

声明
Public Class ContentIterator
用法
Dim instance As ContentIterator

public class ContentIterator

备注

提供帮助器方法，以确保列表可以查询时，控制正在传输的数据量。这是对于大型列表或 Web 场的 queris 特别重要，以便将放在数据库上的负载不是过多。

示例

using System;

using Microsoft.SharePoint;
using Microsoft.Office.Server.Utilities;
using Microsoft.SharePoint.Administration;
using System.IO;

namespace Microsoft.SDK.SharePointServer.Samples
{
    class Program
    {
        static void Main(string[] args)
        {
            // Put your web application URL here
            Uri webApplicationUrl = new Uri("https://localhost:80/");

            // Put your site Url here
            string siteUrl = "https://localhost:80/";

            SPWebApplication webApplication = SPWebApplication.Lookup(webApplicationUrl);

            ContentIteratorCodeSample1.ProcessAllSitesInWebApplication(webApplication);

            using (SPSite siteCollection = new SPSite(siteUrl))
            {
                using (SPWeb site = siteCollection.OpenWeb())
                {
                    ContentIteratorCodeSample2.ProcessAllListItemsInSite(site);

                    FolderHierarchyCodeSample1.ProcessAllFoldersInList(site.Lists["Shared Documents"]);

                    string[] sharedDocumentsFolderUrls = new string[]
                    {
                        "/Shared Documents/folder1",
                        "/Shared Documents/folder2",
                        "/Shared Documents/folder3/subfolder1",
                    };

                    FolderHierarchyCodeSample2.ProcessFoldersFromList(site.Lists["Shared Documents"], sharedDocumentsFolderUrls);

                    string[] webFolderUrls = new string[]
                    {
                        "/Shared Documents/folder1",
                        "/Shared Documents/folder2",
                        "/Shared Documents/folder3/subfolder1",
                        "/Pages/folder1",
                        "/Pages/folder2",
                    };

                    FolderHierarchyCodeSample2.ProcessFoldersFromWeb(site, webFolderUrls);

                    Stream memoryStream = new MemoryStream(Guid.NewGuid().ToByteArray(), false);
                    FolderHierarchyCodeSample2.AddTemplateResource(siteCollection, memoryStream, Guid.NewGuid().ToString());
                }
            }
        }
    }
}

using System;
using System.Globalization;
using System.Text;

using Microsoft.SharePoint;
using Microsoft.Office.Server.Utilities;

using ContentIterator = Microsoft.Office.Server.Utilities.ContentIterator;

namespace Microsoft.SDK.SharePointServer.Samples
{
    // This sample processes all list items in lists which have a Yes/No column named "ShouldProcess"
    public static class ContentIteratorCodeSample2
    {
        // Put your column name here
        private static string columnName = "ShouldProcess";

        // Replace this with your own query
        private static string CreateQuery()
        {
            // This example 
            StringBuilder queryBuilder = new StringBuilder();
            queryBuilder.Append("<Where><Eq>");
            queryBuilder.AppendFormat(CultureInfo.InvariantCulture,
                "<FieldRef Name=\"{0}\" />",
                columnName);
            queryBuilder.Append("<Value Type=\"Boolean\">1</Value>");
            queryBuilder.Append("</Eq></Where>");
            queryBuilder.Append(ContentIterator.ItemEnumerationOrderByNVPField);

            return queryBuilder.ToString();
        }

        private static bool OnListException(SPList list, Exception e)
        {
            // Put your logic here to handle exceptions thrown while
            // processing a list.

            // Do not rethrow exception, keep iterating
            return false;
        }

        private static void ProcessItem(SPListItem item)
        {
            // Put your code here to process a list item
        }

        // This method iterates over every list item in a site that satifies a query
        public static void ProcessAllListItemsInSite(SPWeb site)
        {
            // Put your iterator name here which will be logged in the ULS logs
            string iteratorName = "Sample list item iterator";

            ContentIterator iterator = new ContentIterator(iteratorName);

            iterator.ProcessLists(site.Lists,
                delegate(SPList list)
                {
                    // Only process lists with which have the required column
                    if (!list.Fields.ContainsFieldWithStaticName(columnName))
                        return;

                    ContentIterator.EnsureFieldIndexed(list, list.Fields.GetFieldByInternalName(columnName).Id);

                    // Now iterate over all items in the list that satify the query
                    string query = CreateQuery();

                    ContentIterator itemsIterator = new ContentIterator(iterator);

                    // do a recursive query in all folders
                    itemsIterator.ProcessListItems(list,
                        query,
                        true,  
                        delegate(SPListItemCollection items)
                        {
                            // items is just a single page of results from the query
                            // so iterating over the collection directly is OK
                            foreach (SPListItem item in items)
                            {
                                ProcessItem(item);
                            }
                        },
                        null  // don't handle exceptions
                        );
                },
                delegate(SPList list, Exception e)
                {
                    return OnListException(list, e);
                }
            );
        }
    }
}

线程安全性

该类型的任何公共 静态 (已共享 在 Visual Basic 中) 成员都是线程安全的。不保证任何实例成员都是线程安全的。

另请参阅

引用

ContentIterator 成员

Microsoft.Office.Server.Utilities 命名空间