DataObjectMethodAttribute Class
TOC
Collapse the table of content
Expand the table of content

DataObjectMethodAttribute Class

 

Identifies a data operation method exposed by a type, what type of operation the method performs, and whether the method is the default data method. This class cannot be inherited.

Namespace:   System.ComponentModel
Assembly:  System (in System.dll)

System.Object
  System.Attribute
    System.ComponentModel.DataObjectMethodAttribute

[AttributeUsageAttribute(AttributeTargets.Method)]
public sealed class DataObjectMethodAttribute : Attribute

NameDescription
System_CAPS_pubmethodDataObjectMethodAttribute(DataObjectMethodType)

Initializes a new instance of the DataObjectMethodAttribute class and identifies the type of data operation the method performs.

System_CAPS_pubmethodDataObjectMethodAttribute(DataObjectMethodType, Boolean)

Initializes a new instance of the DataObjectMethodAttribute class, identifies the type of data operation the method performs, and identifies whether the method is the default data method that the data object exposes.

NameDescription
System_CAPS_pubpropertyIsDefault

Gets a value indicating whether the method that the DataObjectMethodAttribute is applied to is the default data method exposed by the data object for a specific method type.

System_CAPS_pubpropertyMethodType

Gets a DataObjectMethodType value indicating the type of data operation the method performs.

System_CAPS_pubpropertyTypeId

When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)

NameDescription
System_CAPS_pubmethodEquals(Object)

Returns a value indicating whether this instance is equal to a specified object.(Overrides Attribute.Equals(Object).)

System_CAPS_pubmethodGetHashCode()

Returns the hash code for this instance.(Overrides Attribute.GetHashCode().)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodIsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)

System_CAPS_pubmethodMatch(Object)

Gets a value indicating whether this instance shares a common pattern with a specified attribute.(Overrides Attribute.Match(Object).)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

You can use the DataObjectMethodAttribute to identify data operation methods on a type marked with the DataObjectAttribute attribute so that they are more easily identified by callers using reflection. When the DataObjectMethodAttribute attribute is applied to a method, it describes the type of operation the method performs and indicates whether the method is the default data operation method of a type. Components such as the ObjectDataSource control and the ObjectDataSourceDesigner class examine the values of this attribute, if present, to help determine which data method to call at run time.

The following code example demonstrates how you can apply the DataObjectMethodAttribute attribute to a publicly exposed method and identify the type of data operation it performs as well as whether it is the type's default data method. In this example the NorthwindData type exposes two data methods: one to retrieve a set of data named GetAllEmployees, and another to delete data named DeleteEmployeeByID. The DataObjectMethodAttribute attribute is applied to both methods, the GetAllEmployees method is marked as the default method for the Select data operation, and the DeleteEmployeeByID method is marked as the default method for the Delete data operation.

[DataObjectAttribute]
public class NorthwindData
{  
  public NorthwindData() {}

  [DataObjectMethodAttribute(DataObjectMethodType.Select, true)]
  public static IEnumerable GetAllEmployees()
  {
    AccessDataSource ads = new AccessDataSource();
    ads.DataSourceMode = SqlDataSourceMode.DataReader;
    ads.DataFile = "~//App_Data//Northwind.mdb";
    ads.SelectCommand = "SELECT EmployeeID,FirstName,LastName FROM Employees";
    return ads.Select(DataSourceSelectArguments.Empty);
  }

  // Delete the Employee by ID.
  [DataObjectMethodAttribute(DataObjectMethodType.Delete, true)]
  public void DeleteEmployeeByID(int employeeID)
  {
    throw new Exception("The value passed to the delete method is "
                         + employeeID.ToString());
  }
}

.NET Framework
Available since 2.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Return to top
Show:
© 2016 Microsoft