LINQ to Entities异常不支持指定的类型成员'Date'

Question

在执行以下语句时出现异常。 DateTime result; if (!DateTime.TryParse(rule.data, out result))     return jobdescriptions; if (result < new DateTime(1754, 1, 1)) // sql can't handle dates before 1-1-1753     return jobdescriptions; return jobdescriptions.Where(j => j.JobDeadline.Date == Convert.ToDateTime(rule.data).Date );例外The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.我知道例外的含义，但我不知道如何摆脱它。有什么帮助吗？

Answer 1

您可以使用EntityFunctions的TruncateTime方法将属性正确转换为SQL：Date

using System.Data.Objects; // you need this namespace for EntityFunctions

// ...

DateTime ruleData = Convert.ToDateTime(rule.data).Date;

return jobdescriptions

    .Where(j => EntityFunctions.TruncateTime(j.JobDeadline) == ruleData);

更新： EntityFunctions在EF6中已弃用，使用DbFunctions.TruncateTime