Entity-framework – The specified type member ‘Date’ is not supported in LINQ to Entities Exception

entity-frameworklinq-to-entities

I got a exception while implementing the following statements.

 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 );

Exception

The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.

I know what the exception means but i don't know how to get rid of it. Any help?

Best Answer

You can use the TruncateTime method of the EntityFunctions to achieve a correct translations of the Date property into SQL:

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);

Update: EntityFunctionsis deprecated in EF6, Use DbFunctions.TruncateTime

Related Solutions

C# – ‘Date’ is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported

If you are using EF 6.0+, you can use DbFunctions.TruncateTime(DateTime?) :

var query =
    from t in context.Logs
    where t.Title == title 
    && DbFunctions.TruncateTime(t.Timestamp) == LogDate.Date
    select t;

Note: For earlier version of EF where DbFunctions isn't available, EntityFunctions.TruncateTime(DateTime?) can be used instead.

The specified type member is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported

You cannot use properties that are not mapped to a database column in a Where expression. You must build the expression based on mapped properties, like:

var date = DateTime.Now.AddYears(-from);
result = result.Where(p => date >= p.DOB);
// you don't need `AsQueryable()` here because result is an `IQueryable` anyway

As a replacement for your not mapped Age property you can extract this expression into a static method like so:

public class clsProfileDate
{
    // ...
    public DateTime DOB { get; set; } // property mapped to DB table column

    public static Expression<Func<clsProfileDate, bool>> IsOlderThan(int age)
    {
        var date = DateTime.Now.AddYears(-age);
        return p => date >= p.DOB;
    }
}

And then use it this way:

result = result.Where(clsProfileDate.IsOlderThan(from));

Best Answer

Related Solutions

C# – ‘Date’ is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported

The specified type member is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported

Related Topic