Query Expression Syntax Examples: Element Operators (LINQ to Entities
The examples in this topic demonstrate how to use the First method to query the AdventureWorks Sales Model using the query expression syntax. The AdventureWorks Sales Model used in these examples is built from the Contact, Address, Product, SalesOrderHeader, and SalesOrderDetail tables in the AdventureWorks sample database.
The examples in this topic use the following using/Imports statements:
Option Explicit On
Option Strict On
Imports L2EExamplesVB.AdventureWorksModel
Imports System.Data.Objects
Imports System.Globalization
using System;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Objects;
using AdventureWorksModel;
using System.Globalization;
For more information, see How to: Create a LINQ to Entities Project in Visual Studio.
First
Example
The following example uses the First method to return the first contact whose first name is "Brooke".
Using AWEntities As New AdventureWorksEntities
Dim contacts As ObjectQuery(Of Contact) = AWEntities.Contact
Dim query As Contact = ( _
From cont In contacts _
Where cont.FirstName = "Brooke" _
Select cont).First()
Console.WriteLine("ContactID: " & query.ContactID)
Console.WriteLine("FirstName: " & query.FirstName)
Console.WriteLine("LastName: " & query.LastName)
End Using
using (AdventureWorksEntities AWEntities = new AdventureWorksEntities())
{
ObjectQuery<Contact> contacts = AWEntities.Contact;
Contact query = (
from contact in contacts
where contact.FirstName == "Brooke"
select contact)
.First();
Console.WriteLine("ContactID: " + query.ContactID);
Console.WriteLine("FirstName: " + query.FirstName);
Console.WriteLine("LastName: " + query.LastName);
}