Question

有谁知道如何制作获得今天所有生日的Linq查询？以下代码不起作用：

var getBirthdays = 
    orgContext.CreateQuery<Contact>()
              .Where(c => c.BirthDate != null 
                          && c.BirthDate.Value.Month == DateTime.Now.Month).ToList();

我收到这样的错误：

“无效”'where'条件。实体成员正在调用无效财产或方法。“

提前致谢！

Answer 1

任何时候供应商撰写关于如何做一件简单的事情的四部分博客系列（如微软在2007年所做的那样），你必须知道这并不简单。据我所知，从那时起，这一点没有更新。

所以你的选择有限：

创建名为new_birthmonth和new_birthday的新字段，每次通过插件创建或更新联系人时都会更新，然后查询这些int字段。
使用Dynamic Linq，在OR子句中构建一个WHERE子句，检查生日是否在合理的年份范围内（例如，140岁的长肝脏）（以下代码）。

List<string> birthdays = new List<string>(); //will contain list of OR clauses

//makes sure no CRM unsupported dates are passed (less than 1/1/1900)
for (int i = Math.Min(140, DateTime.Today.Year - 1900); i > -1; i--) 
{
    //adds a different date per year
    birthdays.Add
    (
        string.Format
        (
            //DateTimes are stored in UTC
            "BirthDate = DateTime.Parse(\"{0}\")",
            DateTime.Today.ToUniversalTime().AddYears(-i)
        )
    );
}

//completes the correct dynamic linq OR clause
string birthdayList = string.Join(" OR ", birthdays);

var getBirthdays = orgContext.CreateQuery<Xrm.Contact>()
    .Where(c => c.BirthDate != null)
    .Where(birthdayList)
    .ToList();

Answer 2

我根据“Peter Majeed”和使用“LinqKit”的例子解决了我的问题！

var predicate = PredicateBuilder.False<Contact>();
for (int i = Math.Min(140, DateTime.Today.Year - 1900); i > -1; i--)
{
    DateTime cleanDateTime = new DateTime(DateTime.Today.AddYears(-i).Year, DateTime.Today.AddYears(-1).Month, DateTime.Today.AddYears(-i).Day);
    predicate = predicate.Or(p => p.BirthDate == cleanDateTime.ToUniversalTime());
}
var getBirthdays = (from c in orgContext.CreateQuery<Contact>().AsExpandable().Where(predicate)
                     select c).ToList();

以上查询给了我正确的结果！感谢所有帮助我的人！

Answer 3

如果c.BirthDate可以为空，则必须先将其转换为日期时间：

var getBirthdays = orgContext.CreateQuery<Contact>()
                             .Where(c => c.BirthDate != null && 
                                     (Convert.ToDateTime(c.BirthDate).Month == 
                                        DateTime.Now.Month) && 
                                      Convert.ToDateTime(c.BirthDate).Day == 
                                        DateTime.Now.Day))
                             .ToList();

Answer 4

如果在您的情况下可以使用查询，您可以使用查询获取此信息吗？

//set up the condition + filter
var ce = new Microsoft.Xrm.Sdk.Query.ConditionExpression();
ce.Operator = Microsoft.Xrm.Sdk.Query.ConditionOperator.LastXDays;
ce.AttributeName = "birthdate";
ce.Values.Add(30);

var fe = new Microsoft.Xrm.Sdk.Query.FilterExpression();
fe.AddCondition(ce);

//build query
var query = new Microsoft.Xrm.Sdk.Query.QueryExpression();
query.EntityName = "contact";
query.Criteria.AddFilter(fe);

//get results
var results = CrmHelperV5.OrgProxy.RetrieveMultiple(query);

//if you want early bound entities, convert here.
var contacts = new List<Contact>();
foreach(var result in results.Entities)
{
    contacts.Add(result.ToEntity<Contact>());
}

You may want to investigate the other operators for the filters + conditions

Answer 5

orgContext.CreateQuery<Contact>().ToList<Contact>().Where...

Answer 6

您可以使用QueryExpression（适用于Microsoft CRM插件）

public EntityCollection getBirthdateList(IOrganizationService orgsService)
    {
        List<string> birthdays = new List<string>(); 

        //makes sure no CRM unsupported dates are passed (less than 1/1/1900)
        for (int i = Math.Min(140, DateTime.Today.Year - 1930); i > -1; i--)
        {
            //adds a different date per year
            birthdays.Add
            (
                DateTime.Now.AddYears(-i).ToString("yyyy-MM-dd")
            ); 
        }

       
        // Instantiate QueryExpression 
        var query = new QueryExpression("contact");

        // Define filter QEquote.Criteria
        var queryfilter = new FilterExpression();
        query.Criteria.AddFilter(queryfilter);

        // Define filter 
        queryfilter.FilterOperator = LogicalOperator.Or;
        queryfilter.AddCondition("birthdate",ConditionOperator.In,birthdays.ToArray());
        return orgsService.RetrieveMultiple(query); ;
    }

如何获得今天的所有生日？

6 个答案: