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Method-Based Query Syntax Examples: Ordering (LINQ to Entities)

The examples in this topic demonstrate how to use the ThenBy method to query the AdventureWorks Sales Model using method-based query 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.

ThenBy

Example

The following example in method-based query syntax uses OrderBy and ThenBy to return a list of contacts ordered by last name and then by first name.

Using AWEntities As New AdventureWorksEntities

    Dim sortedContacts = AWEntities.Contact _
    .OrderBy(Function(c) c.LastName) _
    .ThenBy(Function(c) c.FirstName) _
    .Select(Function(c) c)

    Console.WriteLine("The list of contacts sorted by last name then by first name:")
    For Each sortedContact As Contact In sortedContacts
        Console.WriteLine(sortedContact.LastName + ", " + sortedContact.FirstName)
    Next
End Using
using (AdventureWorksEntities AWEntities = new AdventureWorksEntities())
{
    IQueryable<Contact> sortedContacts = AWEntities.Contact
        .OrderBy(c => c.LastName)
        .ThenBy(c => c.FirstName)
        .Select(c => c);

    Console.WriteLine("The list of contacts sorted by last name then by first name:");
    foreach (Contact sortedContact in sortedContacts)
    {
        Console.WriteLine(sortedContact.LastName + ", " + sortedContact.FirstName);
    }
}

ThenByDescending

Example

The following example uses the OrderBy and ThenByDescending methods to first sort by list price, and then perform a descending sort of the product names.

Using AWEntities As New AdventureWorksEntities
    Dim products As ObjectQuery(Of Product) = AWEntities.Product

    Dim query As IOrderedQueryable(Of Product) = products _
    .OrderBy(Function(prod As Product) prod.ListPrice) _
    .ThenByDescending(Function(prod As Product) prod.Name)

    For Each prod As Product In query
        Console.WriteLine("Product ID: {0} Product Name: {1} List Price {2}", _
            prod.ProductID, _
            prod.Name, _
            prod.ListPrice)
    Next
End Using
using (AdventureWorksEntities AWEntities = new AdventureWorksEntities())
{
    ObjectQuery<Product> products = AWEntities.Product;

    IOrderedQueryable<Product> query = products
        .OrderBy(product => product.ListPrice)
        .ThenByDescending(product => product.Name);

    foreach (Product product in query)
    {
        Console.WriteLine("Product ID: {0} Product Name: {1} List Price {2}",
            product.ProductID,
            product.Name,
            product.ListPrice);
    }
}

See Also

Concepts

Method-Based Query Syntax Examples (LINQ to Entities)