Sorgu İfadesi Söz Dizimi Örnekleri: Bölümleme
Bu konudaki örnekler, sorgu ifadesi söz dizimini Skip kullanarak AdventureWorks Satış Modeli'ni sorgulamak için ve Take yöntemlerinin nasıl kullanılacağını göstermektedir. Bu örneklerde kullanılan AdventureWorks Satış Modeli, AdventureWorks örnek veritabanındaki Contact, Address, Product, SalesOrderHeader ve SalesOrderDetail tablolarından oluşturulur.
Bu konudaki örneklerde aşağıdaki using
/Imports
deyimler kullanılır:
using System;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Objects;
using System.Globalization;
using System.Data.EntityClient;
using System.Data.SqlClient;
using System.Data.Common;
Option Explicit On
Option Strict On
Imports System.Data.Objects
Imports System.Globalization
Atla
Örnek
Aşağıdaki örnek, Seattle'daki Skip ilk iki adres dışında tümünü almak için yöntemini kullanır.
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<Address> addresses = context.Addresses;
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
//LINQ to Entities only supports Skip on ordered collections.
var query = (
from address in addresses
from order in orders
where address.AddressID == order.Address.AddressID
&& address.City == "Seattle"
orderby order.SalesOrderID
select new
{
City = address.City,
OrderID = order.SalesOrderID,
OrderDate = order.OrderDate
}).Skip(2);
Console.WriteLine("All but first 2 orders in Seattle:");
foreach (var order in query)
{
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}",
order.City, order.OrderID, order.OrderDate);
}
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim addresses As ObjectSet(Of Address) = context.Addresses
'LINQ to Entities only supports Skip on ordered collections.
Dim query = ( _
From address In addresses _
From order In orders _
Where address.AddressID = order.Address.AddressID _
And address.City = "Seattle" _
Order By order.SalesOrderID _
Select New With _
{ _
.City = address.City, _
.OrderID = order.SalesOrderID, _
.OrderDate = order.OrderDate _
}).Skip(2)
Console.WriteLine("All but first 2 orders in Seattle:")
For Each order In query
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}", _
order.City, order.OrderID, order.OrderDate)
Next
End Using
Take
Örnek
Aşağıdaki örnek, Seattle'daki Take ilk üç adresi almak için yöntemini kullanır.
String city = "Seattle";
using (AdventureWorksEntities context = new AdventureWorksEntities())
{
ObjectSet<Address> addresses = context.Addresses;
ObjectSet<SalesOrderHeader> orders = context.SalesOrderHeaders;
var query = (
from address in addresses
from order in orders
where address.AddressID == order.Address.AddressID
&& address.City == city
select new
{
City = address.City,
OrderID = order.SalesOrderID,
OrderDate = order.OrderDate
}).Take(3);
Console.WriteLine("First 3 orders in Seattle:");
foreach (var order in query)
{
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}",
order.City, order.OrderID, order.OrderDate);
}
}
Dim city = "Seattle"
Using context As New AdventureWorksEntities
Dim orders As ObjectSet(Of SalesOrderHeader) = context.SalesOrderHeaders
Dim addresses As ObjectSet(Of Address) = context.Addresses
Dim query = ( _
From address In addresses _
From order In orders _
Where address.AddressID = order.Address.AddressID _
And address.City = city _
Select New With _
{ _
.City = address.City, _
.OrderID = order.SalesOrderID, _
.OrderDate = order.OrderDate _
}).Take(3)
Console.WriteLine("First 3 orders in Seattle:")
For Each order In query
Console.WriteLine("City: {0} Order ID: {1} Total Due: {2:d}", _
order.City, order.OrderID, order.OrderDate)
Next
End Using