Mer Hardik Mer Hardik - 3 months ago 12
ASP.NET (C#) Question

Entity Framework selection query

I am making a simple application for insert, update, delete, select data with

Entity Framework


I already made insertion, deletion and select all data.

Now I want to select with where condition with filter of two fields

For ex : I have table with

userid
username
password
email


Now need selection like
where email = "" and password = ""


I know how to write query in SQL but having not clues with
entity framework
.

Also need to store this result in datatable and looping solution both for learning purpose.

This can help many beginners

Answer

Using Linq To Entities with lambda expression:

var result = dBContext.Account.Where(a=> a.email == "" && a.password =="").ToList();

Using Linq To Entities the less fancy way:

var result = (from a in dBContext.Account
              where a.email == "" && a.password ==""
              select a).ToList();

Lambda expressions are used most of the time. Some people find lambda's less readable. I think it's more a personal taste that depends from your background.

EDIT:

dbContext should be replaced by the name you gave your dbContext/Entities when setting up your Entitiy framework EDMX or Code First Classes.

Account should be replaced by the name of your table/Entity

To loop and edit the results you can do:

foreach(var account in results)
{
   //do something with the properties
   account.email = "test@updated.com"
}

//store the changes again in the db
dbContext.SaveChanges();