.NET Framework Class Library
DataLoadOptions..::.LoadWith Method

Retrieves specified data related to the main target.

Overload List

  NameDescription
Public methodLoadWith<(Of <(T>)>)(Expression<(Of <(Func<(Of <(T, Object>)>)>)>))Specifies which sub-objects to retrieve when a query is submitted for an object of type T.
Public methodLoadWith(LambdaExpression)Retrieves specified data related to the main target by using a lambda expression.
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Remarks

Use the LoadWith method to specify which data related to your main target should be retrieved at the same time. For example, if you know you will need information about customers' orders, you can use LoadWith to make sure the order information is retrieved at the same time as the customer information. This approach results in only one trip to the database for both sets of information.

Examples

In the following example, all the Orders for all the Customers who are located in London are retrieved when the query is executed. As a result, successive access to the Orders property on a Customer object does not trigger a new database query.

Visual Basic
Dim db As New Northwnd("c:\northwnd.mdf")

Dim dlo As DataLoadOptions = New DataLoadOptions()
dlo.LoadWith(Of Customer)(Function(c As Customer) c.Orders)
db.LoadOptions = dlo

Dim londonCustomers = _
    From cust In db.Customers _
    Where cust.City = "London" _
    Select cust

For Each custObj In londonCustomers
    Console.WriteLine(custObj.CustomerID)
Next
C#
Northwnd db = new Northwnd(@"c:\northwnd.mdf");
DataLoadOptions dlo = new DataLoadOptions();
dlo.LoadWith<Customer>(c => c.Orders);
db.LoadOptions = dlo;

var londonCustomers =
    from cust in db.Customers
    where cust.City == "London"
    select cust;

foreach (var custObj in londonCustomers)
{
    Console.WriteLine(custObj.CustomerID);
}
See Also

Reference

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Community Content

DeborahK
DataLoadOptions and ExecuteQuery
NOTE: The DataLoadOptions only work when the LINQ to SQL generates the SQL. It will not work in conjunction with ExecuteQuery().
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