linq or ado net

DHL: Error: LINQ to Entities does not support the specified type member "Date" LINQ such as: var v = from L in _dal. Share where l.pingcoid = = Pingcoid (l.createtime.date = = DateTime.Now.Date) select L; return V.tolist (); Error: LINQ to Entities does not support the specified type member "Date". Change to such ok:datetime SDT = DateTime.Now.Date; DateTime dt

types that enumerate the groupings of the items that have been formed, and the groupings themselves are enumerable types, which enumerate the actual items. The sample code is as follows:1 var persons = new[] {//Anonymous type Object array 2 new {name= "Zhang San", sex= "male", age=32,address= "Guangdong Shenzhen"}, 3 new {name= "John Doe", sex= "male", Age=26,addre ss= "Guangdong Guangzhou"}, 4 new {name= "Harry", sex= "female", age=22,address= "Guangdong Shenzhen"}, 5 new {name= "Zhao Liu

Vb.net-based database access-ADO. NET (1) The name of ADO. NET originated from ADO (ActiveX Data Objects) and is a COM component library used to access Ask data. When I first came into contact with ADO.

Microsoft's vision. net is a wide one. in addition to their desire for it to support all programming languages, either directly or through interoperability layers, they also want to bring together all communication frameworks and data storage engines. while WCF is making headway for standardizing communication APIs, their universal data access model Entity Framework is lagging behind. A major problem up until now is that the

connection objects, for different data sources, ADO. NET provides different command objects. Specifically, it can be divided into the following command object. . NET Data provider corresponding Command object . NET Framework Data Provider for OLE DB OleDbCommand Object

Ado. NET Component You can use two components of ADO. Net to access and process data: . NET Framework data provisionProgram . NET Framework data provider The. NET Fr

I recently saw ADO. NET data service in my learning process. It seems to be very useful and I will use it today; At present, his operating mechanism is not very clear. First, let's take an example to feel his benefits; In the later learning process, you may learn more deeply, and enjoy a better understanding of its internal mechanisms; First look at the creation process: 1. Create an ASP. NETProgram

Microsoft has developed a new term, connection mode and disconnection mode. The dataset mode in the memory seems to have been available for a long time, and the clientdataset of Delphi seems to be in this structure. I still haven't seen any innovations in. net. In addition, ADO itself has such a client-disconnected DataSet object recordset. "dataset can manage multiple datasets and Their Relationships." Thi

);// The first parameter indicates the name of the created constraint, the second parameter indicates the column to which the constraint is added, and the third parameter true indicates the primary key constraint and false indicates the uniqueness constraint. Implicitly create a foreign key constraint Datatable. Constraints. Add ("fk_customerid", tblcustomers. Columns ["mermerid"] , Tblorders. Columns ["mermerid"]);// The first parameter represents the constraint name, the second parameter repr