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How to: Turn Off Deferred Loading (LINQ to SQL)

You can turn off deferred loading by setting DeferredLoadingEnabled to false. For more information, see Deferred versus Immediate Loading (LINQ to SQL).

Note

Deferred loading is turned off by implication when object tracking is turned off. For more information, see How to: Retrieve Information As Read-Only (LINQ to SQL).

Example

The following example shows how to turn off deferred loading by setting DeferredLoadingEnabled to false.

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

db.DeferredLoadingEnabled = False 

Dim ds As New DataLoadOptions()
ds.LoadWith(Function(c As Customer) c.Orders)
ds.LoadWith(Of Order)(Function(o) o.OrderDetails)
db.LoadOptions = ds

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

For Each custObj In custQuery
    Console.WriteLine("Customer ID: {0}", custObj.CustomerID)
    For Each ord In custObj.Orders
        Console.WriteLine(vbTab & "Order ID: {0}", ord.OrderID)
        For Each detail In ord.OrderDetails
            Console.WriteLine(vbTab & vbTab & "Product ID: {0}", _
                detail.ProductID)
        Next 
    Next 
Next
Northwnd db = new Northwnd(@"c:\northwnd.mdf");
db.DeferredLoadingEnabled = false;

DataLoadOptions ds = new DataLoadOptions();
ds.LoadWith<Customer>(c => c.Orders);
ds.LoadWith<Order>(o => o.OrderDetails);
db.LoadOptions = ds;

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

foreach (Customer custObj in custQuery)
{
    Console.WriteLine("Customer ID: {0}", custObj.CustomerID);
    foreach (Order ord in custObj.Orders)
    {
        Console.WriteLine("\tOrder ID: {0}", ord.OrderID);
        foreach (OrderDetail detail in ord.OrderDetails)
        {
            Console.WriteLine("\t\tProduct ID: {0}", detail.ProductID);
        }
    }
}

See Also

Other Resources

Query Concepts in LINQ to SQL

Querying the Database (LINQ to SQL)