Dynamics Crm 2015：值不能為空。\\ r \\ n參數名稱：詳細信息

Question

我正在嘗試集成Dynamics Crm2015。在這篇與Microsoft Dynamic CRM 2011集成的文章的幫助下，我編寫了以下代碼：

Dictionary<string, string> parameters = GetCustomParameters(company.Id);
Uri uri = new Uri(parameters["serviceUrl"]);
var username = parameters["username"];
var password = parameters["password"];
var entity = parameters["entity"];
ClientCredentials credentials = new ClientCredentials();
credentials.UserName.UserName = username;
credentials.UserName.Password = password;

OrganizationServiceProxy osproxy = new OrganizationServiceProxy(uri, null, credentials, null);
IOrganizationService _services = (IOrganizationService)osproxy;
QueryExpression query = new QueryExpression()
{
    EntityName = entity,
    ColumnSet = new ColumnSet("firstname", "lastname", "emailaddress")
};

EntityCollection retrieved = _services.RetrieveMultiple(query);

當我執行此操作時，它提示：

值不能為空。\\ r \\ n參數名稱：詳細信息

任何幫助，將不勝感激。 我以前沒有CRM集成方面的經驗。

Answer 1

此QueryExpression測試的工作方式類似於CRM 2016

這是一個例子

ConditionExpression condicion1 = new ConditionExpression();
            condicion1.AttributeName = "name";
            condicion1.Operator = ConditionOperator.NotNull;

            FilterExpression filtro = new FilterExpression();
            filtro.Conditions.Add(condicion1);
            filtro.FilterOperator = LogicalOperator.And;

            QueryExpression consulta = new QueryExpression("account");
            consulta.Criteria.AddFilter(filtro);
            consulta.ColumnSet = new ColumnSet("name", "telephone1");

            EntityCollection resultados = service.RetrieveMultiple(consulta);

            foreach (Entity c in resultados.Entities)
            {
                Console.WriteLine("{0} | {1}", c["name"].ToString(), c["telephone1"].ToString());
            }
            Console.Read();