示例：将 FetchXML 与分页 Cookie 结合使用
发布日期： 2017年1月
适用于： Dynamics 365 (online),Dynamics 365 (on-premises),Dynamics CRM 2016,Dynamics CRM Online
此示例代码适用于 Microsoft Dynamics 365（在线或本地）。下载 Microsoft Dynamics CRM SDK 包。 它可能位于下载包的以下位置：
SampleCode\CS\GeneralProgramming\Queries\FetchPagingWithCookie.cs
要求
有关运行此 SDK 中提供的示例代码的要求的详细信息，请参阅使用示例和帮助程序代码。
示例
此示例演示如何在 FetchXML 查询中使用分页 Cookie 检索连续的查询结果页面。 它使用 IOrganizationService。RetrieveMultiple 方法。
using System;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using System.IO;
// These namespaces are found in the Microsoft.Xrm.Sdk.dll assembly
// found in the SDK\bin folder.
using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Client;
using Microsoft.Xrm.Sdk.Query;
using Microsoft.Xrm.Sdk.Discovery;
// This namespace is found in Microsoft.Crm.Sdk.Proxy.dll assembly
// found in the SDK\bin folder.
using Microsoft.Crm.Sdk.Messages;
using Microsoft.Xrm.Sdk.Messages;
namespace Microsoft.Crm.Sdk.Samples
{
/// <summary>
/// Demonstrates how to use the Fetch XML method with a paging
/// cookie to retrieve a batch of records.
/// If you want to run this sample repeatedly, you have the option to
/// delete all the records created at the end of execution.
/// </summary>
class FetchPagingWithCookie
{
#region Class Level Members
/// <summary>
/// Stores the organization service proxy.
/// </summary>
private OrganizationServiceProxy _serviceProxy;
private IOrganizationService _service;
// Define the IDs needed for this sample.
public Guid _parentAccountId;
public Guid[] _childAccountIds;
#endregion Class Level Members
#region How To Sample Code
/// <summary>
/// Create and configure the organization service proxy.
/// Create a parent account record and subsequent 10 child account records.
/// Retrieve batch of records using RetrieveMultiple message with paging cookie.
/// Optionally delete any entity records that were created for this sample.
/// </summary>
/// <param name="serverConfig">Contains server connection information.</param>
/// <param name="promptForDelete">When True, the user will be prompted to delete all
/// created entities.</param>
public void Run(ServerConnection.Configuration serverConfig, bool promptForDelete)
{
try
{
// Connect to the Organization service.
// The using statement assures that the service proxy will be properly disposed.
using (_serviceProxy = new OrganizationServiceProxy(serverConfig.OrganizationUri, serverConfig.HomeRealmUri,serverConfig.Credentials, serverConfig.DeviceCredentials))
{
// This statement is required to enable early-bound type support.
_serviceProxy.EnableProxyTypes();
_service = (IOrganizationService)_serviceProxy;
// Call the method to create any data that this sample requires.
CreateRequiredRecords();
// Define the fetch attributes.
// Set the number of records per page to retrieve.
int fetchCount = 3;
// Initialize the page number.
int pageNumber = 1;
// Initialize the number of records.
int recordCount = 0;
// Specify the current paging cookie. For retrieving the first page,
// pagingCookie should be null.
string pagingCookie = null;
// Create the FetchXml string for retrieving all child accounts to a parent account.
// This fetch query is using 1 placeholder to specify the parent account id
// for filtering out required accounts. Filter query is optional.
// Fetch query also includes optional order criteria that, in this case, is used
// to order the results in ascending order on the name data column.
string fetchXml = string.Format(@"<fetch version='1.0'
mapping='logical'
output-format='xml-platform'>
<entity name='account'>
<attribute name='name' />
<attribute name='emailaddress1' />
<order attribute='name' descending='false'/>
<filter type='and'>
<condition attribute='parentaccountid'
operator='eq' value='{0}' uiname='' uitype='' />
</filter>
</entity>
</fetch>",
_parentAccountId);
Console.WriteLine("Retrieving data in pages\n");
Console.WriteLine("#\tAccount Name\t\t\tEmail Address");
while (true)
{
// Build fetchXml string with the placeholders.
string xml = CreateXml(fetchXml, pagingCookie, pageNumber, fetchCount);
// Excute the fetch query and get the xml result.
RetrieveMultipleRequest fetchRequest1 = new RetrieveMultipleRequest
{
Query = new FetchExpression(xml)
};
EntityCollection returnCollection = ((RetrieveMultipleResponse)_service.Execute(fetchRequest1)).EntityCollection;
foreach (var c in returnCollection.Entities)
{
System.Console.WriteLine("{0}.\t{1}\t\t{2}", ++recordCount, c.Attributes["name"], c.Attributes["emailaddress1"] );
}
// Check for morerecords, if it returns 1.
if (returnCollection.MoreRecords)
{
Console.WriteLine("\n****************\nPage number {0}\n****************", pageNumber);
Console.WriteLine("#\tAccount Name\t\t\tEmail Address");
// Increment the page number to retrieve the next page.
pageNumber++;
// Set the paging cookie to the paging cookie returned from current results.
pagingCookie = returnCollection.PagingCookie;
}
else
{
// If no more records in the result nodes, exit the loop.
break;
}
}
DeleteRequiredRecords(promptForDelete);
}
}
// Catch any service fault exceptions that Microsoft Dynamics CRM throws.
catch (FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault>)
{
// You can handle an exception here or pass it back to the calling method.
throw;
}
return;
}
public string ExtractNodeValue(XmlNode parentNode, string name)
{
XmlNode childNode = parentNode.SelectSingleNode(name);
if (null == childNode)
{
return null;
}
return childNode.InnerText;
}
public string ExtractAttribute(XmlDocument doc, string name)
{
XmlAttributeCollection attrs = doc.DocumentElement.Attributes;
XmlAttribute attr = (XmlAttribute)attrs.GetNamedItem(name);
if (null == attr)
{
return null;
}
return attr.Value;
}
public string CreateXml(string xml, string cookie, int page, int count)
{
StringReader stringReader = new StringReader(xml);
XmlTextReader reader = new XmlTextReader(stringReader);
// Load document
XmlDocument doc = new XmlDocument();
doc.Load(reader);
return CreateXml(doc, cookie, page, count);
}
public string CreateXml(XmlDocument doc, string cookie, int page, int count)
{
XmlAttributeCollection attrs = doc.DocumentElement.Attributes;
if (cookie != null)
{
XmlAttribute pagingAttr = doc.CreateAttribute("paging-cookie");
pagingAttr.Value = cookie;
attrs.Append(pagingAttr);
}
XmlAttribute pageAttr = doc.CreateAttribute("page");
pageAttr.Value = System.Convert.ToString(page);
attrs.Append(pageAttr);
XmlAttribute countAttr = doc.CreateAttribute("count");
countAttr.Value = System.Convert.ToString(count);
attrs.Append(countAttr);
StringBuilder sb = new StringBuilder(1024);
StringWriter stringWriter = new StringWriter(sb);
XmlTextWriter writer = new XmlTextWriter(stringWriter);
doc.WriteTo(writer);
writer.Close();
return sb.ToString();
}
/// <summary>
/// This method creates any entity records that this sample requires.
/// Create a parent account record.
/// Create 10 child accounts to the parent account record.
/// </summary>
public void CreateRequiredRecords()
{
// Instantiate a account entity record and set its property values.
// See the Entity Metadata topic in the SDK documentation
// to determine which attributes must be set for each entity.
// Create the parent account.
Account parentAccount = new Account
{
Name = "Root Test Account",
EMailAddress1 = "root@root.com"
};
_parentAccountId = _service.Create(parentAccount);
// Create 10 child accounts.
_childAccountIds = new Guid[10];
int count = 1;
while (true)
{
Account childAccount = new Account
{
Name = "Child Test Account " + count.ToString(),
EMailAddress1 = "child" + count.ToString() + "@root.com",
EMailAddress2 = "same@root.com",
ParentAccountId = new EntityReference(Account.EntityLogicalName, _parentAccountId)
};
_childAccountIds[count - 1] = _service.Create(childAccount);
// Jump out of the loop after creating 10 child accounts.
if (count == 10)
break;
// Increment the count.
count++;
}
return;
}
/// <summary>
/// Deletes any entity records that were created for this sample.
/// <param name="prompt">Indicates whether to prompt the user to delete the records created in this sample.</param>
/// </summary>
public void DeleteRequiredRecords(bool prompt)
{
bool deleteRecords = true;
if (prompt)
{
Console.WriteLine("\nDo you want these entity records deleted? (y/n)");
String answer = Console.ReadLine();
deleteRecords = (answer.StartsWith("y") || answer.StartsWith("Y"));
}
if (deleteRecords)
{
// Remove the test parent account.
_service.Delete(Account.EntityLogicalName, _parentAccountId);
// Remove 10 test child accounts.
int deleteCount = 0;
while (deleteCount < 10)
{
_service.Delete(Account.EntityLogicalName, _childAccountIds[deleteCount]);
++deleteCount;
}
Console.WriteLine("Entity records have been deleted.");
}
}
#endregion How To Sample Code
#region Main
/// <summary>
/// Standard Main() method used by most SDK samples.
/// </summary>
/// <param name="args"></param>
static public void Main(string[] args)
{
try
{
// Obtain the target organization's Web address and client logon
// credentials from the user.
ServerConnection serverConnect = new ServerConnection();
ServerConnection.Configuration config = serverConnect.GetServerConfiguration();
FetchPagingWithCookie app = new FetchPagingWithCookie();
app.Run(config, true);
}
catch (FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault> ex)
{
Console.WriteLine("The application terminated with an error.");
Console.WriteLine("Timestamp: {0}", ex.Detail.Timestamp);
Console.WriteLine("Code: {0}", ex.Detail.ErrorCode);
Console.WriteLine("Message: {0}", ex.Detail.Message);
Console.WriteLine("Plugin Trace: {0}", ex.Detail.TraceText);
Console.WriteLine("Inner Fault: {0}",
null == ex.Detail.InnerFault ? "No Inner Fault" : "Has Inner Fault");
}
catch (System.TimeoutException ex)
{
Console.WriteLine("The application terminated with an error.");
Console.WriteLine("Message: {0}", ex.Message);
Console.WriteLine("Stack Trace: {0}", ex.StackTrace);
Console.WriteLine("Inner Fault: {0}",
null == ex.InnerException.Message ? "No Inner Fault" : ex.InnerException.Message);
}
catch (System.Exception ex)
{
Console.WriteLine("The application terminated with an error.");
Console.WriteLine(ex.Message);
// Display the details of the inner exception.
if (ex.InnerException != null)
{
Console.WriteLine(ex.InnerException.Message);
FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault> fe = ex.InnerException
as FaultException<Microsoft.Xrm.Sdk.OrganizationServiceFault>;
if (fe != null)
{
Console.WriteLine("Timestamp: {0}", fe.Detail.Timestamp);
Console.WriteLine("Code: {0}", fe.Detail.ErrorCode);
Console.WriteLine("Message: {0}", fe.Detail.Message);
Console.WriteLine("Plugin Trace: {0}", fe.Detail.TraceText);
Console.WriteLine("Inner Fault: {0}",
null == fe.Detail.InnerFault ? "No Inner Fault" : "Has Inner Fault");
}
}
}
// Additional exceptions to catch: SecurityTokenValidationException, ExpiredSecurityTokenException,
// SecurityAccessDeniedException, MessageSecurityException, and SecurityNegotiationException.
finally
{
Console.WriteLine("Press <Enter> to exit.");
Console.ReadLine();
}
}
#endregion Main
}
}
另请参阅
IOrganizationService
RetrieveMultiple
使用 FetchXML 构建查询
示例：在Fetch和QueryExpression之间转换查询
帮助程序代码：ServerConnection 类
使用 FetchXML 聚合
使用 FetchXML 构建查询
Microsoft Dynamics 365
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