DataServiceContext.UpdateObject(Object) Method

Reference

Definition

Namespace:: System.Data.Services.Client

Assembly:: System.Data.Services.Client.dll

Important

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Changes the state of the specified object in the DataServiceContext to Modified.

public:
 void UpdateObject(System::Object ^ entity);

public void UpdateObject (object entity);

member this.UpdateObject : obj -> unit

Public Sub UpdateObject (entity As Object)

Parameters

entity: Object

The tracked entity to be assigned to the Modified state.

Exceptions

ArgumentNullException

When entity is null.

ArgumentException

When entity is in the Detached state.

Examples

The following example retrieves and modifies an existing object and then calls the UpdateObject method on the DataServiceContext to mark the item in the context as updated. An HTTP MERGE message is sent to the data service when SaveChanges is called. This example uses the DataServiceContext generated by the Add Service Reference tool based on the Northwind data service, which is created when you complete the WCF Data Services .

string customerId = "ALFKI";

// Create the DataServiceContext using the service URI.
NorthwindEntities context = new NorthwindEntities(svcUri);

// Get a customer to modify using the supplied ID.
var customerToChange = (from customer in context.Customers
                        where customer.CustomerID == customerId
                        select customer).Single();

// Change some property values.
customerToChange.CompanyName = "Alfreds Futterkiste";
customerToChange.ContactName = "Maria Anders";
customerToChange.ContactTitle = "Sales Representative";

try
{
    // Mark the customer as updated.
    context.UpdateObject(customerToChange);

    // Send the update to the data service.
    context.SaveChanges();
}
catch (DataServiceRequestException  ex)
{
    throw new ApplicationException(
        "An error occurred when saving changes.", ex);
}

Dim customerId = "ALFKI"

' Create the DataServiceContext using the service URI.
Dim context = New NorthwindEntities(svcUri)

' Get a customer to modify using the supplied ID.
Dim customerToChange = (From customer In context.Customers _
                        Where customer.CustomerID = customerId _
                        Select customer).Single()

' Change some property values.
customerToChange.CompanyName = "Alfreds Futterkiste"
customerToChange.ContactName = "Maria Anders"
customerToChange.ContactTitle = "Sales Representative"

Try
    ' Mark the customer as updated.
    context.UpdateObject(customerToChange)

    ' Send the update to the data service.
    context.SaveChanges()
Catch ex As DataServiceRequestException
    Throw New ApplicationException( _
            "An error occurred when saving changes.", ex)
End Try

Applies to

Dela via