Beispiel: Weitere LINQ-Abfragenbeispiele

Dieser Beispielcode ist für Dynamics 365 for Customer Engagement. Laden Sie das vollständige Beispiel herunter von Beispiel: Arbeiten mit Abfragen.

Anforderungen

Um das Beispielprojekt herunterzuladen und die NuGet-Pakete wiederherzustellen, die im Beispielprojekt verwendet werden, ist eine Internetverbindung erforderlich.

Anforderungen

Weitere Informationen zu den Anforderungen für die Ausführung des hier bereitgestellten Beispielcodes finden Sie unter Ausführen eines einfachen Programms mit Customer Engagement-Webservices und So führen Sie Dataverse-Beispiele aus.

Veranschaulichung

Dieses Beispiel zeigt, wie Sie .NET Language-Integrated Query (LINQ)-Abfragen erstellen. Die folgenden Abfragen werden veranschaulicht:

• Rufen Sie Datensätze mit Skip/Take-Datensatzauslagerungen auf.

• Verwenden Sie orderBy, um abgerufene Elemente zu bestellen.

• Filtern Sie mehrere Entitäten mit LINQ.

• Erstellen Sie eine komplexe Abfrage mit LINQ.

Beispiel

using System;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel;

// These namespaces are found in the Microsoft.Xrm.Sdk.dll assembly
// located in the SDK\bin folder of the SDK download.
using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Client;

namespace Microsoft.Crm.Sdk.Samples
{
 /// <summary>
 /// Demonstrates how to make LINQ queries with the OrganizationServiceContext
 /// object and strongly-typed entities.</summary>
 /// <remarks>
 /// At run-time, you will be given the option to delete all the
 /// database records created by this program.</remarks>
 public class UseLinqQuery
 {
  #region Class Level Members

  private List<Guid> _accountIds = new List<Guid>();
  private List<Guid> _contactIds = new List<Guid>();
  private List<Guid> _leadIds = new List<Guid>();
  private List<Guid> _taskIds = new List<Guid>();
  private OrganizationServiceProxy _serviceProxy;
  private IOrganizationService _service;

  #endregion Class Level Members

  #region How To Sample Code
  /// <summary>
  /// This method first connects to the Organization service and service context.
  /// Afterwards, several LINQ query techniques are demonstrated.
  /// </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;

     CreateRequiredRecords();

     ServiceContext svcContext =
         new ServiceContext(_service);


     // Retrieve records with Skip/Take record paging. Setting a page size
     // can help you manage your Skip and Take calls, since Skip must be
     // passed a multiple of Take's parameter value.
     int pageSize = 5;

     var accountsByPage = (from a in svcContext.AccountSet
                           select new Account
                           {
                            Name = a.Name,
                           });
     System.Console.WriteLine("Skip 10 accounts, then Take 5 accounts");
     System.Console.WriteLine("======================================");
     foreach (var a in accountsByPage.Skip(2 * pageSize).Take(pageSize))
     {
      System.Console.WriteLine(a.Name);
     }
     System.Console.WriteLine();
     System.Console.WriteLine("<End of Listing>");
     System.Console.WriteLine();
     //OUTPUT:
     //Skip 10 accounts, then Take 5 accounts
     //======================================
     //Fourth Coffee 6
     //Fourth Coffee 7
     //Fourth Coffee 8
     //Fourth Coffee 9
     //Fourth Coffee 10

     //<End of Listing>



     // Use orderBy to order items retrieved.
     var orderedAccounts = from a in svcContext.AccountSet
                           orderby a.Name
                           select new Account
                           {
                            Name = a.Name,
                           };
     System.Console.WriteLine("Display accounts ordered by name");
     System.Console.WriteLine("================================");
     foreach (var a in orderedAccounts)
     {
      System.Console.WriteLine(a.Name);
     }
     System.Console.WriteLine();
     System.Console.WriteLine("<End of Listing>");
     System.Console.WriteLine();
     //OUTPUT:
     //Display accounts ordered by name
     //================================
     //A. Datum Corporation
     //Adventure Works
     //Coho Vineyard
     //Fabrikam
     //Fourth Coffee 1
     //Fourth Coffee 10
     //Fourth Coffee 2
     //Fourth Coffee 3
     //Fourth Coffee 4
     //Fourth Coffee 5
     //Fourth Coffee 6
     //Fourth Coffee 7
     //Fourth Coffee 8
     //Fourth Coffee 9
     //Humongous Insurance

     //<End of Listing>


     // Filter multiple entities using LINQ.
     var query = from c in svcContext.ContactSet
                 join a in svcContext.AccountSet
                               on c.ContactId equals a.PrimaryContactId.Id
                 where c.LastName == "Wilcox" || c.LastName == "Andrews"
                 where a.Address1_Telephone1.Contains("(206)")
                     || a.Address1_Telephone1.Contains("(425)")
                 select new
                 {
                  Contact = new Contact
                  {
                   FirstName = c.FirstName,
                   LastName = c.LastName,
                  },
                  Account = new Account
                  {
                   Address1_Telephone1 = a.Address1_Telephone1
                  }
                 };

     Console.WriteLine("Join account and contact");
     Console.WriteLine("List all records matching specified parameters");
     Console.WriteLine("Contact name: Wilcox or Andrews");
     Console.WriteLine("Account area code: 206 or 425");
     Console.WriteLine("==============================================");
     foreach (var record in query)
     {
      Console.WriteLine("Contact Name: {0} {1}",
          record.Contact.FirstName, record.Contact.LastName);
      Console.WriteLine("Account Phone: {0}",
          record.Account.Address1_Telephone1);
     }
     Console.WriteLine("<End of Listing>");
     Console.WriteLine();
     //OUTPUT:
     //Join account and contact
     //List all records matching specified parameters
     //Contact name: Wilcox or Andrews
     //Account area code: 206 or 425
     //==============================================
     //Contact Name: Ben Andrews
     //Account Phone: (206)555-5555
     //Contact Name: Ben Andrews
     //Account Phone: (425)555-5555
     //Contact Name: Colin Wilcox
     //Account Phone: (425)555-5555
     //<End of Listing>



     // Build a complex query with LINQ. This query includes multiple
     // JOINs and a complex WHERE statement.
     var complexQuery = from c in svcContext.ContactSet
                        join a in svcContext.AccountSet
                               on c.ContactId equals a.PrimaryContactId.Id
                        join l in svcContext.CreateQuery<Lead>()
                               on a.OriginatingLeadId.Id equals l.LeadId
                        where c.LastName == "Wilcox" || c.LastName == "Andrews"
                        where a.Address1_Telephone1.Contains("(206)")
                            || a.Address1_Telephone1.Contains("(425)")
                        select new
                        {
                         Contact = new Contact
                         {
                          FirstName = c.FirstName,
                          LastName = c.LastName,
                         },
                         Account = new Account
                         {
                          Address1_Telephone1 = a.Address1_Telephone1
                         },
                         Lead = new Lead
                         {
                          LeadId = l.LeadId
                         }
                        };

     Console.WriteLine("Join account, contact and lead");
     Console.WriteLine("List all records matching specified parameters");
     Console.WriteLine("Contact name: Wilcox or Andrews");
     Console.WriteLine("Account area code: 206 or 425");
     Console.WriteLine("==============================================");
     foreach (var record in complexQuery)
     {
      Console.WriteLine("Lead ID: {0}",
          record.Lead.LeadId);
      Console.WriteLine("Contact Name: {0} {1}",
          record.Contact.FirstName, record.Contact.LastName);
      Console.WriteLine("Account Phone: {0}",
          record.Account.Address1_Telephone1);
     }
     Console.WriteLine("<End of Listing>");
     Console.WriteLine();
     //OUTPUT:
     //Join account, contact and lead
     //List all records matching specified parameters
     //Contact name: Wilcox or Andrews
     //Account area code: 206 or 425
     //==============================================
     //Lead ID: 78d5df14-64a3-e011-aea3-00155dba3818
     //Contact Name: Colin Wilcox
     //Account Phone: (425)555-5555
     //<End of Listing>

     //Retrieve a related Task for a Contact
     //Shows requirement that LoadProperty must be used to access the related record.
     Contact benAndrews = svcContext.ContactSet.Where(c => c.FullName == "Ben Andrews").FirstOrDefault();
     if (benAndrews != null)
     {
      //benAndrews.Contact_Tasks is null until LoadProperty is used.
      svcContext.LoadProperty(benAndrews, "Contact_Tasks");
      Task benAndrewsFirstTask = benAndrews.Contact_Tasks.FirstOrDefault();
      if (benAndrewsFirstTask != null)
      {
       Console.WriteLine("Ben Andrews first task with Subject: '{0}' retrieved.", benAndrewsFirstTask.Subject);
      }
     }

     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;
   }
  }

  /// <summary>
  /// Creates any entity records that this sample requires.
  /// </summary>
  public void CreateRequiredRecords()
  {
   // Create 3 contacts.
   Contact contact = new Contact()
   {
    FirstName = "Ben",
    LastName = "Andrews",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Redmond",
    Address1_StateOrProvince = "WA"
   };
   Guid benAndrewsContactId = _service.Create(contact);
   _contactIds.Add(benAndrewsContactId);
   
   //Create a task associated with Ben Andrews
   Task task = new Task() { 
    Subject = "Sample Task", 
    RegardingObjectId = new EntityReference() { 
     LogicalName = Contact.EntityLogicalName,
     Id = benAndrewsContactId, 
     Name = contact.FullName 
    } 
   };
   _taskIds.Add(_service.Create(task));
  


   contact = new Contact()
   {
    FirstName = "Colin",
    LastName = "Wilcox",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Bellevue",
    Address1_StateOrProvince = "WA"
   };
   _contactIds.Add(_service.Create(contact));

   contact = new Contact()
   {
    FirstName = "Ben",
    LastName = "Smith",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Bellevue",
    Address1_StateOrProvince = "WA"
   };
   _contactIds.Add(_service.Create(contact));

   // Create 3 leads.
   Lead lead = new Lead()
   {
    FirstName = "Dan",
    LastName = "Wilson",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Redmond",
    Address1_StateOrProvince = "WA"
   };
   _leadIds.Add(_service.Create(lead));

   lead = new Lead()
   {
    FirstName = "Jim",
    LastName = "Wilson",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Bellevue",
    Address1_StateOrProvince = "WA"
   };
   _leadIds.Add(_service.Create(lead));

   lead = new Lead()
   {
    FirstName = "Denise",
    LastName = "Smith",
    EMailAddress1 = "sample@example.com",
    Address1_City = "Bellevue",
    Address1_StateOrProvince = "WA"
   };
   _leadIds.Add(_service.Create(lead));

   // Create 5 customized Accounts for the LINQ samples.
   Account account = new Account
   {
    Name = "A. Datum Corporation",
    Address1_StateOrProvince = "Colorado",
    Address1_Telephone1 = "(206)555-5555",
    PrimaryContactId =
        new EntityReference(Contact.EntityLogicalName, _contactIds[0])
   };
   _accountIds.Add(_service.Create(account));

   account = new Account
   {
    Name = "Adventure Works",
    Address1_StateOrProvince = "Illinois",
    Address1_County = "Lake County",
    Address1_Telephone1 = "(206)555-5555",
    OriginatingLeadId =
        new EntityReference(Lead.EntityLogicalName, _leadIds[0])
   };
   _accountIds.Add(_service.Create(account));

   account = new Account
   {
    Name = "Coho Vineyard",
    Address1_StateOrProvince = "Washington",
    Address1_County = "King County",
    Address1_Telephone1 = "(425)555-5555",
    PrimaryContactId =
        new EntityReference(Contact.EntityLogicalName, _contactIds[1]),
    OriginatingLeadId =
        new EntityReference(Lead.EntityLogicalName, _leadIds[0])
   };
   _accountIds.Add(_service.Create(account));

   account = new Account
   {
    Name = "Fabrikam",
    Address1_StateOrProvince = "Washington",
    Address1_Telephone1 = "(425)555-5555",
    PrimaryContactId =
        new EntityReference(Contact.EntityLogicalName, _contactIds[0])
   };
   _accountIds.Add(_service.Create(account));

   account = new Account
   {
    Name = "Humongous Insurance",
    Address1_StateOrProvince = "Missouri",
    Address1_County = "Saint Louis County",
    Address1_Telephone1 = "(314)555-5555",
    PrimaryContactId =
        new EntityReference(Contact.EntityLogicalName, _contactIds[1])
   };
   _accountIds.Add(_service.Create(account));

   // Create 10 basic Account records.
   for (int i = 1; i <= 10; i++)
   {
    account = new Account
    {
     Name = "Fourth Coffee " + i,
     Address1_StateOrProvince = "California"
    };
    _accountIds.Add(_service.Create(account));
   }
  }

  /// <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 toBeDeleted = true;

   if (prompt)
   {
    // Ask the user if the created entities should be deleted.
    Console.Write("\nDo you want these entity records deleted? (y/n) [y]: ");
    String answer = Console.ReadLine();
    if (answer.StartsWith("y") ||
        answer.StartsWith("Y") ||
        answer == String.Empty)
    {
     toBeDeleted = true;
    }
    else
    {
     toBeDeleted = false;
    }
   }

   if (toBeDeleted)
   {
    // Delete all records created in this sample.


    foreach (Guid taskId in _taskIds)
    {
     _service.Delete(Task.EntityLogicalName, taskId);
    }
    foreach (Guid accountId in _accountIds)
    {
     _service.Delete(Account.EntityLogicalName, accountId);
    }
    foreach (Guid contactId in _contactIds)
    {
     _service.Delete(Contact.EntityLogicalName, contactId);
    }
    foreach (Guid leadId in _leadIds)
    {
     _service.Delete(Lead.EntityLogicalName, leadId);
    }
    Console.WriteLine("Entity record(s) have been deleted.");
   }
  }

  #endregion How To Sample Code

  #region Main method

  /// <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();

    UseLinqQuery app = new UseLinqQuery();
    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 method
 }
}

Siehe auch

Erstellen von Abfragen mit LINQ (.NET Language-integrierte Abfrage)
Beispiel: Verwenden von LINQ mit später Bindung
OrganizationServiceContext