检索实体清单 [英] Retrieving list of Entities

问题描述

在CRM 2011中，我可以使用EarlyBoundEntities进行常规的创建，更新，删除操作.但是，我似乎找不到使用相同类型的代码检索实体列表的示例.有没有办法使用EarlyBoundEntities检索类型的项目列表?

In CRM 2011 I can do the usual Create, Update, Delete operations using EarlyBoundEntities. I cant, however, seem to find an example of retrieving a list of entities using the same type of code. Is there a way of retrieving a list of items of type using EarlyBoundEntities?

我已经查看了MSDN，如果我已经知道它的GUID，我所能找到的就是如何检索它.

I've looked through MSDN and all I can find is how to retrieve an Entity if I know its GUID already.

 // Retrieve the account containing several of its attributes.
 ColumnSet cols = new ColumnSet(
                new String[] { "name", "address1_postalcode", "lastusedincampaign" });

 Account retrievedAccount = (Account)_service.Retrieve("account", _accountId, cols);
 Console.Write("retrieved, ");

例如，我如何获取所有没有电话号码的帐户的列表?

How would I for example get a list of all accounts which didnt have a phone number?

推荐答案

如果已经使用servicecontextname参数生成了早期绑定的代理类，则可以使用LINQ进行查询.

If you've generated your early-bound proxy classes with the servicecontextname parameters, then you could LINQ for querying.

var context = new XrmServiceContext(service);
var accounts = context.AccountSet.Where(item => item.Telephone1 == null);

否则，如果您仍想使用其他查询方法(例如QueryExpression)，则可以使用LINQ将所有实例转换为所需的早绑定类型.

Otherwise, if you still wanted to use other query methods such as QueryExpression you could use LINQ to cast all instances to the desire early-bound type.

var contacts = service.RetrieveMultiple(new QueryExpression
                                            {
                                                EntityName = "contact",
                                                ColumnSet = new ColumnSet("firstname")
                                            })
    .Entities
    .Select(item => item.ToEntity<Contact>());

如果您愿意，也可以使用扩展方法:

You could also use an extension method if you'd prefer:

public static IEnumerable<T> RetrieveMultiple<T>(this IOrganizationService service, QueryBase query) where T : Entity
{
    return service.RetrieveMultiple(query)
        .Entities
        .Select(item => item.ToEntity<T>());
}

用法:

var contacts = service.RetrieveMultiple<Contact>(new QueryExpression
                                                        {
                                                            EntityName = "contact",
                                                            ColumnSet = new ColumnSet("firstname")
                                                        });

这篇关于检索实体清单的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！