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DataObjectAttribute Class

Definition

Identifies a type as an object suitable for binding to an ObjectDataSource object. This class cannot be inherited.

public ref class DataObjectAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Class)]
public sealed class DataObjectAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Class)>]
type DataObjectAttribute = class
    inherit Attribute
Public NotInheritable Class DataObjectAttribute
Inherits Attribute
Inheritance
DataObjectAttribute
Attributes

Examples

The following code example demonstrates how you can apply the DataObjectAttribute attribute to indicate an object is suitable for binding to an ObjectDataSource object. In this example, the NorthwindData object is intended for use with an ObjectDataSource object.

[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());
  }
}
<DataObjectAttribute()> _
Public Class NorthwindData

  <DataObjectMethodAttribute(DataObjectMethodType.Select, True)> _
  Public Shared Function GetAllEmployees() As IEnumerable
    Dim ads As 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)
  End Function 'GetAllEmployees

  ' Delete the Employee by ID.
  <DataObjectMethodAttribute(DataObjectMethodType.Delete, True)> _
  Public Sub DeleteEmployeeByID(ByVal employeeID As Integer)
    Throw New Exception("The value passed to the delete method is " + employeeID.ToString())
  End Sub

End Class

Remarks

Use the DataObjectAttribute attribute to identify an object as suitable for use by an ObjectDataSource object. Design-time classes such as the ObjectDataSourceDesigner class use the DataObjectAttribute attribute to present suitable objects to bind to an ObjectDataSource object.

For more information about using attributes, see Attributes.

Constructors

DataObjectAttribute()

Initializes a new instance of the DataObjectAttribute class.

DataObjectAttribute(Boolean)

Initializes a new instance of the DataObjectAttribute class and indicates whether an object is suitable for binding to an ObjectDataSource object.

Fields

DataObject

Indicates that the class is suitable for binding to an ObjectDataSource object at design time. This field is read-only.

Default

Represents the default value of the DataObjectAttribute class, which indicates that the class is suitable for binding to an ObjectDataSource object at design time. This field is read-only.

NonDataObject

Indicates that the class is not suitable for binding to an ObjectDataSource object at design time. This field is read-only.

Properties

IsDataObject

Gets a value indicating whether an object should be considered suitable for binding to an ObjectDataSource object at design time.

TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object)

Determines whether this instance of DataObjectAttribute fits the pattern of another object.

GetHashCode()

Returns the hash code for this instance.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

Gets a value indicating whether the current value of the attribute is the default value for the attribute.

Match(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

(Inherited from Attribute)
_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)
_Attribute.GetTypeInfoCount(UInt32)

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

(Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Applies to