示例：创建 LINQ 查询
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\CreateALinqQuery.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。
演示
此示例演示如何创建简单 .NET 语言集成查询 (LINQ) 查询。 演示的查询有：
检索呼叫用户有权访问的所有客户。
检索可以读取客户但不姓“Cannon”的用户所负责的所有客户。
返回所有在其地址中指定了地区的客户的计数。
返回我们在其中拥有客户的省/市/自治区的计数。 它使用了 distinct 关键字，该关键字对省/市/自治区仅计数一次。
返回城市为“Redmond”，且名为“Joe”或“John.”的联系人。
示例
using System;
using System.ServiceModel;
using System.Linq;
using System.Collections.Generic;
// 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 do create basic LINQ queries against Microsoft Dynamics CRM
/// records.</summary>
/// <remarks>
/// At run-time, you will be given the option to delete all the
/// database records created by this program.</remarks>
public class CreateALinqQuery
{
#region Class Level Members
private Dictionary<Guid, String> _recordIds = new Dictionary<Guid, String>();
private OrganizationServiceProxy _serviceProxy;
private IOrganizationService _service;
#endregion Class Level Members
#region How To Sample Code
/// <summary>
/// This method first connects to the Organization service. Afterwards,
/// basic LINQ queries are performed.
/// </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();
// Create the ServiceContext object that will generate
// the IQueryable collections for LINQ calls.
ServiceContext svcContext = new ServiceContext(_service);
// Loop through all CRM account using the IQueryable interface
// on the ServiceContext object
var accounts = from a in svcContext.AccountSet
select new Account
{
Name = a.Name,
Address1_County = a.Address1_County
};
System.Console.WriteLine("List all accounts in CRM");
System.Console.WriteLine("========================");
foreach (var a in accounts)
{
System.Console.WriteLine(a.Name + " " + a.Address1_County);
}
System.Console.WriteLine();
System.Console.WriteLine("<End of Listing>");
System.Console.WriteLine();
//OUTPUT:
//List all accounts in CRM
//========================
//Fourth Coffee
//School of Fine Art Lake County
//Tailspin Toys King County
//Woodgrove Bank
//Contoso, Ltd. Saint Louis County
//<End of Listing>
System.Console.WriteLine();
// Retrieve all accounts owned by the user who has read access rights
// to the accounts and where the last name of the user is not Cannon.
var queryAccounts = from a in svcContext.AccountSet
join owner in svcContext.SystemUserSet
on a.OwnerId.Id equals owner.SystemUserId
where owner.LastName != "Cannon"
select new Account
{
Name = a.Name,
Address1_City = a.Address1_City
};
System.Console.WriteLine("Accounts not owned by user w/ last name 'Cannon'");
System.Console.WriteLine("================================================");
foreach (var a in queryAccounts)
{
System.Console.WriteLine(a.Name + " " + a.Address1_County);
}
System.Console.WriteLine();
System.Console.WriteLine("<End of Listing>");
System.Console.WriteLine();
//OUTPUT:
//Accounts not owned by user w/ last name 'Cannon'
//================================================
//Fourth Coffee
//School of Fine Art
//Tailspin Toys
//Woodgrove Bank
//Contoso, Ltd.
//<End of Listing>
System.Console.WriteLine();
// Return a count of all accounts which have a county specified
// in their address.
int accountsWithCounty = (from a in svcContext.AccountSet
where (a.Address1_County != null)
select new Account
{
Name = a.Name,
Address1_City = a.Address1_City
}).ToArray().Count();
System.Console.Write("Number of accounts with a county specified: ");
System.Console.WriteLine(accountsWithCounty);
System.Console.WriteLine();
//OUTPUT:
//Number of accounts with a county specified: 3
System.Console.WriteLine();
// Return a count of states in which we have an account. This
// uses the 'distinct' keyword which counts a state only one time.
int statesWithAccounts = (from a in svcContext.AccountSet
where (a.Address1_StateOrProvince != null)
select a.Address1_StateOrProvince)
.Distinct().ToArray().Count();
System.Console.Write("Number of unique states that contain accounts: ");
System.Console.WriteLine(statesWithAccounts);
System.Console.WriteLine();
//OUTPUT:
//Number of unique states that contain accounts: 3
System.Console.WriteLine();
// Return contacts where the city equals Redmond AND the first
// name is Joe OR John.
var queryContacts = from c in svcContext.ContactSet
where (c.Address1_City == "Redmond") &&
(c.FirstName.Equals("Joe") ||
c.FirstName.Equals("John"))
select new Contact
{
FirstName = c.FirstName,
LastName = c.LastName,
Address1_City = c.Address1_City
};
System.Console.WriteLine("Contacts in Redmond named Joe OR John");
System.Console.WriteLine("=====================================");
foreach (var c in queryContacts)
{
System.Console.WriteLine(c.FirstName + " " +
c.LastName + " " + c.Address1_City);
}
System.Console.WriteLine();
System.Console.WriteLine("<End of Listing>");
System.Console.WriteLine();
//OUTPUT:
//Contacts in Redmond named Joe OR John
//=====================================
//Joe Redmond
//John Redmond
//Joe Redmond
//<End of Listing>
System.Console.WriteLine();
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 5 Accounts and 5 Contacts for the LINQ samples.
Account account = new Account
{
Name = "Fourth Coffee",
Address1_StateOrProvince = "Colorado",
};
_recordIds.Add(_service.Create(account), Account.EntityLogicalName);
account = new Account
{
Name = "School of Fine Art",
Address1_StateOrProvince = "Illinois",
Address1_County = "Lake County"
};
_recordIds.Add(_service.Create(account), Account.EntityLogicalName);
account = new Account
{
Name = "Tailspin Toys",
Address1_StateOrProvince = "Washington",
Address1_County = "King County",
};
_recordIds.Add(_service.Create(account), Account.EntityLogicalName);
account = new Account
{
Name = "Woodgrove Bank",
Address1_StateOrProvince = "Washington"
};
_recordIds.Add(_service.Create(account), Account.EntityLogicalName);
account = new Account
{
Name = "Contoso, Ltd.",
Address1_County = "Saint Louis County"
};
_recordIds.Add(_service.Create(account), Account.EntityLogicalName);
Contact contact = new Contact
{
FirstName = "Joe",
Address1_City = "Redmond",
};
_recordIds.Add(_service.Create(contact), Contact.EntityLogicalName);
contact = new Contact
{
FirstName = "John",
Address1_City = "Redmond",
};
_recordIds.Add(_service.Create(contact), Contact.EntityLogicalName);
contact = new Contact
{
FirstName = "John",
Address1_City = "Cleveland",
};
_recordIds.Add(_service.Create(contact), Contact.EntityLogicalName);
contact = new Contact
{
FirstName = "Joe",
Address1_City = "Redmond",
};
_recordIds.Add(_service.Create(contact), Contact.EntityLogicalName);
contact = new Contact
{
FirstName = "Jim",
Address1_City = "Redmond",
};
_recordIds.Add(_service.Create(contact), Contact.EntityLogicalName);
}
/// <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 (var record in _recordIds)
{
_service.Delete(record.Value, record.Key);
}
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();
CreateALinqQuery app = new CreateALinqQuery();
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
}
}
另请参阅
OrganizationServiceContext
使用 LINQ（.NET 语言集成查询）构建查询
示例：复杂的 LINQ 查询
Microsoft Dynamics 365
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