Join on one to many relation in entity framework

Question

0.00/5 (No votes)

See more:

hello
I want to code a join on one to many relation in Entity Framework and Have access to both table fields but I cant, the join in SQL is :

SQL

SELECT        Letter.Text, Users.UserName, Users.ID
FROM            Letter INNER JOIN
                         Users ON Letter.UserID = Users.ID

but in Entity Framework, I have no access to the field "Text" which is in "Letter" Table.

code for Entity Framework:

C#

_TestEntities.Users.select( c => new JoinTable {c.UserName, c.Letter. Text });

I have no access to "text". and JoinTable is a class:

C#

public partial class JoinTable 
        {
            public int ID{ get; set; }
            public string UserName{ get; set; }
            public partial Letter _Letter{ get; set; }
        }

Thanks in advance

What I have tried:

I have tried code above in EF, But it wont let me access to letter Table Fields such as Text

Posted 20-Oct-16 4:22am

Ali Majed HA

Updated 20-Oct-16 5:37am

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

P_Z · Answer 1 · 2016-10-20T05:37:00

Hi,

Maybe you can try such as:

C#

var data = (from user in _TestEntities.Users
            select new JoinTable
            {
                ID = user.ID,
                UserName = user.UserName,
                Letter = new Letter() 
                    {
                       //not sure about the nested object when projecting but still to get the idea
                       Text = user.Letters.FirstOrDefault().Text
                    }  
            });
//Then iterate results ex
foreach(var row in data
{
  //etc
}

This is referred to as Linq projection, see link Query Expression Syntax Examples: Projection (LINQ to DataSet)[^]