使用 DynamicsCRM 中的插件获取 EntityReference 的 GUID

Question

这个问题与我现在为 Dynamics CRM 2011 创建的插件有关。

我有一个具有 5 个属性的实体。其中一个属性是对另一个实体的查找。

我试图用我的插件做的是检索查找实体的 Guid。很简单，对吧？

但不，这给我带来了麻烦，我尝试了数十种使用 EntityReference 来获取 guid 的方法，但都失败了。我尝试创建一个 preImage，但也失败了。

这是代码的片段。

Entity entity = (Entity)context.InputParameters["Target"];

   if (entity.LogicalName == "new_producttaxrate")
  {
   if (entity.Attributes.Contains("new_product"))
     {

     EntityReference ownerLookup = (EntityReference)entity.Attributes["new_product"];
      productName = ownerLookup.Name;
      Guid  productId = ownerLookup.Id;

    }
  }

也想出了这个

     if (entity.Attributes.Contains("new_producttaxrateid"))
              {
                  Guid myGuid = (Guid)entity.Attributes["new_producttaxrateid"];
                  EntityReference ownerLookup = new EntityReference("new_product", myGuid);
                   pid = ownerLookup.Id;
               }

我不断收到这个错误

    Unhandled Exception: System.ServiceModel.FaultException`1[[Microsoft.Xrm.Sdk.OrganizationServiceFault, Microsoft.Xrm.Sdk, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]]: Condition for attribute 'new_producttaxrate.new_product': expected argument(s) of type 'System.Guid' but received 'System.DBNull'.Detail: 
<OrganizationServiceFault xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/xrm/2011/Contracts">
  <ErrorCode>-2147220989</ErrorCode>
  <ErrorDetails xmlns:d2p1="http://schemas.datacontract.org/2004/07/System.Collections.Generic">
    <KeyValuePairOfstringanyType>
      <d2p1:key>CallStack</d2p1:key>
      <d2p1:value xmlns:d4p1="http://www.w3.org/2001/XMLSchema" i:type="d4p1:string">   at Microsoft.Crm.Extensibility.VersionedPluginProxyStepBase.Execute(PipelineExecutionContext context)
   at Microsoft.Crm.Extensibility.Pipeline.Execute(PipelineExecutionContext context)
   at Microsoft.Crm.Extensibility.MessageProcessor.Execute(PipelineExecutionContext context)
   at Microsoft.Crm.Extensibility.InternalMessageDispatcher.Execute(PipelineExecutionContext context)
   at Microsoft.Crm.Extensibility.ExternalMessageDispatcher.ExecuteInternal(IInProcessOrganizationServiceFactory serviceFactory, IPlatformMessageDispatcherFactory dispatcherFactory, String messageName, String requestName, Int32 primaryObjectTypeCode, Int32 secondaryObjectTypeCode, ParameterCollection fields, CorrelationToken correlationToken, CallerOriginToken originToken, UserAuth userAuth, Guid callerId, Guid transactionContextId, Int32 invocationSource, Nullable`1 requestId, Version endpointVersion)
   at Microsoft.Crm.Extensibility.OrganizationSdkServiceInternal.ExecuteRequest(OrganizationRequest request, CorrelationToken correlationToken, CallerOriginToken callerOriginToken, WebServiceType serviceType)
   at Microsoft.Crm.Extensibility.OrganizationSdkServiceInternal.Execute(OrganizationRequest request, CorrelationToken correlationToken, CallerOriginToken callerOriginToken, WebServiceType serviceType)</d2p1:value>
    </KeyValuePairOfstringanyType>
  </ErrorDetails>
  <Message>Condition for attribute 'new_producttaxrate.new_product': expected argument(s) of type 'System.Guid' but received 'System.DBNull'.</Message>
  <Timestamp>2011-03-17T13:21:04.6999035Z</Timestamp>
  <InnerFault i:nil="true" />
  <TraceText>

[VATPlugin2: VATPlugin2.TaxRateValidation]
[4b0b7f5c-9950-e011-849d-000c292be099: VATPlugin2.TaxRateValidation: Create of new_producttaxrate]


</TraceText>
</OrganizationServiceFault>

Answer 1

     if (entity.Attributes.Contains("new_product"))
                   {

                       productGUID = ((EntityReference)entity["new_product"]).Id;
                       Entity member = service.Retrieve("product", ((EntityReference)entity["new_product"]).Id, new ColumnSet(true));
                       if (member.Attributes.Contains("name"))
                       {
                           productName = member.Attributes["name"].ToString();
                       }
                   }

Answer 2

“new columnSet(true)”是不好的做法。请仅传递您想要的字段。