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Sample: Use QueryExpression with a paging cookie

 

Applies To: Dynamics 365 (online), Dynamics 365 (on-premises), Dynamics CRM 2016, Dynamics CRM Online

This sample code is for Microsoft Dynamics 365 (online & on-premises). Download the Microsoft Dynamics CRM SDK package. It can be found in the following location in the download package:

SampleCode\CS\GeneralProgramming\Queries\QueryExpressionPagingWithCookie.cs

Requirements

For more information about the requirements for running the sample code provided in this SDK, see Use the sample and helper code.

Example

This sample shows how to use the paging cookie in a QueryExpression query to retrieve successive pages of query results. It uses the IOrganizationService.RetrieveMultiple method.


using System;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.Collections.Generic;

// 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 QueryExpression 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 QueryExpressionPagingWithCookie
    {
        #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[] _childAccountIds;
        public Guid _parentAccountId;

        #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();

                    // Query using the paging cookie.
                    // Define the paging attributes.
                    // The number of records per page to retrieve.
                    int queryCount = 3;

                    // Initialize the page number.
                    int pageNumber = 1;

                    // Initialize the number of records.
                    int recordCount = 0;

                    // Define the condition expression for retrieving records.
                    ConditionExpression pagecondition = new ConditionExpression();
                    pagecondition.AttributeName = "parentaccountid";
                    pagecondition.Operator = ConditionOperator.Equal;
                    pagecondition.Values.Add(_parentAccountId);

                    // Define the order expression to retrieve the records.
                    OrderExpression order = new OrderExpression();
                    order.AttributeName = "name";
                    order.OrderType = OrderType.Ascending;

                    // Create the query expression and add condition.
                    QueryExpression pagequery = new QueryExpression();
                    pagequery.EntityName = "account";
                    pagequery.Criteria.AddCondition(pagecondition);
                    pagequery.Orders.Add(order);
                    pagequery.ColumnSet.AddColumns("name", "emailaddress1");                   

                    // Assign the pageinfo properties to the query expression.
                    pagequery.PageInfo = new PagingInfo();
                    pagequery.PageInfo.Count = queryCount;
                    pagequery.PageInfo.PageNumber = pageNumber;

                    // The current paging cookie. When retrieving the first page, 
                    // pagingCookie should be null.
                    pagequery.PageInfo.PagingCookie = null;
                    Console.WriteLine("Retrieving sample account records in pages...\n");
                    Console.WriteLine("#\tAccount Name\t\tEmail Address"); 

                    while (true)
                    {
                        // Retrieve the page.
                        EntityCollection results = _serviceProxy.RetrieveMultiple(pagequery);
                        if (results.Entities != null)
                        {
                            // Retrieve all records from the result set.
                            foreach (Account acct in results.Entities)
                            {
                                Console.WriteLine("{0}.\t{1}\t{2}", ++recordCount, acct.Name,
                                                   acct.EMailAddress1);
                            }
                        }

                        // Check for more records, if it returns true.
                        if (results.MoreRecords)
                        {
                            Console.WriteLine("\n****************\nPage number {0}\n****************", pagequery.PageInfo.PageNumber);
                            Console.WriteLine("#\tAccount Name\t\tEmail Address");

                            // Increment the page number to retrieve the next page.
                            pagequery.PageInfo.PageNumber++;

                            // Set the paging cookie to the paging cookie returned from current results.
                            pagequery.PageInfo.PagingCookie = results.PagingCookie;
                        }
                        else
                        {
                            // If no more records are 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;
        }

        /// <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()
        {
            Console.WriteLine("Creating sample account records...\n");

            // 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)
            {
                Console.WriteLine("Delting entity records... please wait!");

                // Remove 10 test child accounts.
                int deleteCount = 0;
                while (deleteCount < 10)
                {
                    _service.Delete(Account.EntityLogicalName, _childAccountIds[deleteCount]);
                    ++deleteCount;
                }

                // Remove the test parent account.
                _service.Delete(Account.EntityLogicalName, _parentAccountId);

                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();

                QueryExpressionPagingWithCookie app = new QueryExpressionPagingWithCookie();
                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

    }
}

See Also

IOrganizationService
Page large result sets with QueryExpression
Build queries with QueryExpression
Sample: Convert queries between Fetch and QueryExpression
Helper code: ServerConnection class

Microsoft Dynamics 365

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