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DataLoadOptions.AssociateWith<T> Method (Expression<Func<T, Object>>)

Filters objects retrieved for a particular relationship.

Namespace:  System.Data.Linq
Assembly:  System.Data.Linq (in System.Data.Linq.dll)

public void AssociateWith<T>(
	Expression<Func<T, Object>> expression
)

Type Parameters

T

The type that is queried against.

If the type is unmapped, an exception is thrown.

Parameters

expression
Type: System.Linq.Expressions.Expression<Func<T, Object>>

Identifies the query to be used on a particular one-to-many field or property. Note the following:

If the expression does not start with a field or property that represents a one-to-many relationship, an exception is thrown.

If an operator other than a valid operator appears in the expression, an exception is thrown. Valid operators are as follows:

Where

OrderBy

ThenBy

OrderByDescending

ThenByDescending

Take

For information about how to avoid cycles, see DataLoadOptions.

In the following example, the inner loop iterates only over those Orders that have not been shipped today.

Northwnd db = new Northwnd(@"c:\northwnd.mdf");
DataLoadOptions dlo = new DataLoadOptions();
dlo.AssociateWith<Customer>(c => c.Orders.Where(p => p.ShippedDate != DateTime.Today));
db.LoadOptions = dlo;
var custOrderQuery = 
    from cust in db.Customers
    where cust.City == "London" 
    select cust;

foreach (Customer custObj in custOrderQuery)
{
    Console.WriteLine(custObj.CustomerID);
    foreach (Order ord in custObj.Orders)
    {
        Console.WriteLine("\t {0}",ord.OrderDate);
    } 
}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5

.NET Framework Client Profile

Supported in: 4

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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