Entity Framework 6 ToString(), formatting (DateTime format), query intercept - entity-framework

Question

I`m not found correct way to search with linq2sql in DateTime (DateTime?) fields.
db.Items.Where(x => x.DateTime1.ToString().Contains("2014.08"))
Not work, because in linq2sql create CAST([XXXX.DateTime1] AS NVARCHAR(MAX)) = '04 Aug 2014' NOT 2014.08
I try use custom function mapping, but no result

Answer 1

Why don't you just use the Year and Month property? You should be able to convert the string input into Year and Month number. Then you do something like:
db.Items.Where(x =>
x.DateTime1.Value.Year == 2014
&& x.DateTime1.Value.Month == 8)
It will simply be converted to:
WHERE (2014 = (DATEPART (year, [Extent1].[Date])))
AND (8 = (DATEPART (month, [Extent1].[Date])))
update
You can use SqlFunctions.DatePart and DbFunctions.Right to produce following format yyyy.mm.dd.
db.Items.Where(x =>
(SqlFunctions.DatePart("yyyy", x.DateTime) + "."
+ DbFunctions.Right("0" + SqlFunctions.DatePart("m", x.DateTime1), 2) + "."
+ DbFunctions.Right("0" + SqlFunctions.DatePart("d", x.DateTime1), 2))
.Contains("2014.08"));

Answer 2

Function in MS SQL
CREATE FUNCTION [dbo].[ToString](#P sql_variant)
RETURNS NVARCHAR(20)
AS
BEGIN
IF (sql_variant_property(#P, 'BaseType') = 'datetime')
RETURN CONVERT(NVARCHAR(10), #P, 102) + ' ' + CONVERT(NVARCHAR(8), #P, 108);
RETURN CAST(#P as NVARCHAR(max));
END
Create sql execution Interceptor
public class DbCommandInterceptor : IDbCommandInterceptor
{
public void ReaderExecuting(DbCommand command, DbCommandInterceptionContext<DbDataReader> interceptionContext)
{
if (command.CommandText.IndexOf("CAST") != -1)
{
command.CommandText = command.CommandText.Replace("CAST(", "dbo.ToString(");
command.CommandText = command.CommandText.Replace("] AS nvarchar(max))", "])");
}
}
}
Add Interceptor to DbContext
public class DB : DbContext
{
public DB(): base(#"Data Source=localhost\SQLEXPRESS;Initial Catalog=EFTest")
{
DbInterception.Add(new DbCommandInterceptor ());
}
}