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ConstructionEnabledAttribute Class

Definition

Enables COM+ object construction support. This class cannot be inherited.

public ref class ConstructionEnabledAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Class, Inherited=true)]
[System.Runtime.InteropServices.ComVisible(false)]
public sealed class ConstructionEnabledAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Class, Inherited=true)>]
[<System.Runtime.InteropServices.ComVisible(false)>]
type ConstructionEnabledAttribute = class
    inherit Attribute
Public NotInheritable Class ConstructionEnabledAttribute
Inherits Attribute
Inheritance
ConstructionEnabledAttribute
Attributes

Examples

The following code example demonstrates the use of this attribute to associate an object constructor string with a ServicedComponent class.

// Accept a constructor string.

[ConstructionEnabled]
public ref class EmployeeInformation: public ServicedComponent
{
private:

   // The employee's user name and salary.
   String^ accountName;
   double salary;

public:

   // Get the employee's name. All users can call this method.
   String^ GetName()
   {
      return (accountName);
   }

   // Set the employee's salary. Only managers can do this.
   void SetSalary( double ammount )
   {
      if ( SecurityCallContext::CurrentCall->IsCallerInRole( "Manager" ) )
      {
         salary = ammount;
      }
      else
      {
         throw gcnew UnauthorizedAccessException;
      }
   }

   // Get the employee's salary. Only the employee and managers can do this.
   double GetSalary()
   {
      if ( SecurityCallContext::CurrentCall->DirectCaller->AccountName == accountName || SecurityCallContext::CurrentCall->IsCallerInRole( "Manager" ) )
      {
         return (salary);
      }
      else
      {
         throw gcnew UnauthorizedAccessException;
      }
   }

protected:
   // Use the constructor string.
   // This method is called when the object is instantiated.
   virtual void Construct( String^ constructorString ) override
   {
      accountName = constructorString;
   }
};
// Accept a constructor string.
[ConstructionEnabled]

public class EmployeeInformation : ServicedComponent
{

    // The employee's user name and salary.
    private string accountName;
    private double salary = 0;

    // Get the employee's name. All users can call this method.
    public string GetName ()
    {
      return(accountName);
    }

    // Set the employee's salary. Only managers can do this.
    public void SetSalary (double ammount)
    {
        if (SecurityCallContext.CurrentCall.IsCallerInRole("Manager"))
        {
            salary = ammount;
        }
        else
        {
            throw new UnauthorizedAccessException();
        }
    }

    // Get the employee's salary. Only the employee and managers can do this.
    public double GetSalary ()
    {
        if ( SecurityCallContext.CurrentCall.DirectCaller.AccountName == accountName ||
             SecurityCallContext.CurrentCall.IsCallerInRole("Manager") )
        {
            return(salary);
        }
        else
        {
          throw new UnauthorizedAccessException();
        }
    }

    // Use the constructor string.
    // This method is called when the object is instantiated.
    protected override void Construct (string constructorString)
    {
        accountName = constructorString;
    }
}
' Accept a constructor string.
<ConstructionEnabled()>  _
Public Class EmployeeInformation
    
    Inherits ServicedComponent
    
    ' The employee's user name and salary.
    Private accountName As String
    Private salary As Double = 0
    
    ' Get the employee's name. All users can call this method.
    Public Function GetName() As String 
        Return accountName
    
    End Function 'GetName
    
    ' Set the employee's salary. Only managers can do this.
    Public Sub SetSalary(ByVal ammount As Double) 
        If SecurityCallContext.CurrentCall.IsCallerInRole("Manager") Then
            salary = ammount
        Else
            Throw New UnauthorizedAccessException()
        End If
    
    End Sub
    
    ' Get the employee's salary. Only the employee and managers can do this.
    Public Function GetSalary() As Double 
        If SecurityCallContext.CurrentCall.DirectCaller.AccountName = accountName OrElse SecurityCallContext.CurrentCall.IsCallerInRole("Manager") Then
            Return salary
        Else
            Throw New UnauthorizedAccessException()
        End If
    
    End Function 'GetSalary
    
    ' Use the constructor string.
    ' This method is called when the object is instantiated.
    Protected Overrides Sub Construct(ByVal constructorString As String) 
        accountName = constructorString
    
    End Sub

End Class

Remarks

For a list of initial property values for an instance of ConstructionEnabledAttribute, see the ConstructionEnabledAttribute constructor.

For more information about using attributes, see Attributes.

Constructors

ConstructionEnabledAttribute()

Initializes a new instance of the ConstructionEnabledAttribute class and initializes the default settings for Enabled and Default.

ConstructionEnabledAttribute(Boolean)

Initializes a new instance of the ConstructionEnabledAttribute class, setting Enabled to the specified value.

Properties

Default

Gets or sets a default value for the constructor string.

Enabled

Gets or sets a value indicating whether COM+ object construction support is enabled.

TypeId

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

(Inherited from Attribute)

Methods

Equals(Object)

Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)
GetHashCode()

Returns the hash code for this instance.

(Inherited from Attribute)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(Inherited from 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