具体来说,我通过此调用检索实体,属性和关系元数据：

var entityRequest = new RetrieveAllEntitiesRequest
                        {
                           RetrieveAsIfPublished = true,EntityFilters = EntityFilters.Entity | EntityFilters.Attributes | EntityFilters.Relationships
                           };
 
var entityResponse = (RetrieveAllEntitiesResponse)_organizationService.Execute(entityRequest);
return entityResponse.EntityMetadata.ToList();

稍后,在使用从该调用返回的EntityMetadata对象时,我检查Attributes集合和LookupAttributeMetadata对象,我尝试使用LookupAttributeMetadata对象的Targets属性来确定查找引用的实体.

但是,在某些情况下,LookupAttributeMetadata对象具有空Targets集合.例如,活动活动(逻辑名称：campaignactivity)实体将Service字段(逻辑名称：服务)定义为Lookup字段,但LookupAttributeMetadata对象中的Targets属性为空.

当我查看实体的Web UI自定义屏幕并打开服务字段时,类型部分显示类型：查找,目标记录类型：帐户,关系名称：campaignactivity_account.

这些信息来自哪里？

另请注意：在活动活动或帐户实体上没有名为“campaignactivity_account”的关系.

更新：
我正在运行Dynamics CRM 2011汇总8的库存安装(尽管我也在Rolloup 7上看到这一点).虽然“广告系列活动”是我在示例中使用的字段,但总共有14个这个问题,如下所列.我正在寻找一个通用的解决方案(对于一个一次性的解决方案),以避免在我的代码中有一堆if(entityName ==“rollupfield”& fieldName ==“organizationid”)…逻辑,因为我正在使用的实体和字段是由用户在运行时选择的,我不一定提前知道我将被交付.

>实体：汇总字段(汇总字段)字段：组织标识(organizationid)
>实体：汇总查询(goalrollupquery)字段：拥有用户(拥有用户)
>实体：进程日志(工作流日志)字段：关于(关于对象)
>实体：已保存的视图(userquery)字段：父查询(parentqueryid)
>实体：广告系列活动(campaignactivity)字段：服务(serviceid)
>实体：电子邮件搜索(emailsearch)字段：父(parentobjectid)
>实体：时区定义(timezonedefinition)字段：组织(organizationid)
>实体：广告系列响应(campaignresponse)字段：服务(serviceid)
>实体：快速运动(批量操作)领域：服务(serviceid)
>实体：字段许可(fieldpermission)字段：组织标识(organizationid)
>实体：时区本地化名称(timezonelocalizedname)字段：组织(organizationid)
>实体：时区规则(timezonerule)字段：组织(organizationid)
>实体：审计(审计)字段：记录(objectid)
>实体：帖子(帖子)字段：关于对象(aboutobjectid)

更新：
以下控制台应用程序可用于重现此问题.

//Requires the following Referenses:
// Microsoft.CSharp
// Microsoft.IdentityModel
// Microsoft.xrm.sdk
// System
// System.Core
// System.Data
// System.Runtime.Serialization
// System.ServiceModel
 
using System;
using System.Linq;
using System.Net;
using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Client;
using Microsoft.Xrm.Sdk.Messages;
using Microsoft.Xrm.Sdk.Metadata;
 
namespace TargetlessLookupsPOC
{
    internal static class Program
    {
        private const string OrganizationServiceURL =
            "http://dynamicscrm1/DynamicsCRM1/XRMServices/2011/Organization.svc";
 
        private static void Main(string[] args)
        {
            Console.WriteLine("====== Authenticating ");
 
            var organizationServiceMngt =
                ServiceConfigurationFactory.CreateManagement<IOrganizationService>(new Uri(OrganizationServiceURL));
            var authCred = new AuthenticationCredentials();
            authCred.ClientCredentials.Windows.ClientCredential = new NetworkCredential();
            IOrganizationService orgProxy = new OrganizationServiceProxy(organizationServiceMngt,authCred.ClientCredentials);
 
            Console.WriteLine("====== Fetching All Entity Metadata ");
            var entityRequest = new RetrieveAllEntitiesRequest
                {
                    RetrieveAsIfPublished = true,EntityFilters = EntityFilters.Entity | EntityFilters.Attributes | EntityFilters.Relationships
                };
 
            var entityResponse = (RetrieveAllEntitiesResponse) orgProxy.Execute(entityRequest);
 
            Console.WriteLine("====== Searching For Targetless Lookups ");
            foreach (var ent in entityResponse.EntityMetadata)
            {
                foreach (var field in ent.Attributes
                    .OfType<LookupAttributeMetadata>()
                    .Where(lookup => !lookup.Targets.Any()))
                {
                    Console.WriteLine("Entity: {0} ({1}),Field: {2} ({3}) (type: {4}) is targetless",ent.DisplayName.LabelText(),ent.LogicalName,field.DisplayName.LabelText(),field.LogicalName,field.AttributeType);
                }
            }
 
            Console.WriteLine("=========================== Done");
            Console.WriteLine("** Press any key to continue **");
            Console.ReadKey();
        }
 
        public static string LabelText(this Label label)
        {
            return (label != null && label.UserLocalizedLabel != null)
                       ? label.UserLocalizedLabel.Label
                       : "<no label>";
        }
    }
}