CommonAcl Class
Collapse the table of content
Expand the table of content

CommonAcl Class


Represents an access control list (ACL) and is the base class for the DiscretionaryAcl and SystemAcl classes.

Namespace:   System.Security.AccessControl
Assembly:  mscorlib (in mscorlib.dll)

public abstract class CommonAcl : GenericAcl


Gets the length, in bytes, of the binary representation of the current CommonAcl object. This length should be used before marshaling the access control list (ACL) into a binary array by using the GetBinaryForm method.(Overrides GenericAcl.BinaryLength.)


Gets the number of access control entries (ACEs) in the current CommonAcl object.(Overrides GenericAcl.Count.)


Gets a Boolean value that specifies whether the access control entries (ACEs) in the current CommonAcl object are in canonical order.


Sets whether the CommonAcl object is a container.


Sets whether the current CommonAcl object is a directory object access control list (ACL).


This property is always set to false. It is implemented only because it is required for the implementation of the ICollection interface.(Inherited from GenericAcl.)


Gets or sets the CommonAce at the specified index.(Overrides GenericAcl.Item[Int32].)


Gets the revision level of the CommonAcl.(Overrides GenericAcl.Revision.)


This property always returns null. It is implemented only because it is required for the implementation of the ICollection interface.(Inherited from GenericAcl.)

System_CAPS_pubmethodCopyTo(GenericAce[], Int32)

Copies each GenericAce of the current GenericAcl into the specified array.(Inherited from GenericAcl.)


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetBinaryForm(Byte[], Int32)

Marshals the contents of the CommonAcl object into the specified byte array beginning at the specified offset.(Overrides GenericAcl.GetBinaryForm(Byte[], Int32).)


Retrieves an object that you can use to iterate through the access control entries (ACEs) in an access control list (ACL).(Inherited from GenericAcl.)


Serves as the default hash function. (Inherited from Object.)


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


Creates a shallow copy of the current Object.(Inherited from Object.)


Removes all access control entries (ACEs) contained by this CommonAcl object that are associated with the specified SecurityIdentifier object.


Removes all inherited access control entries (ACEs) from this CommonAcl object.


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

System_CAPS_pubinterfaceSystem_CAPS_privmethodICollection.CopyTo(Array, Int32)

Copies each GenericAce of the current GenericAcl into the specified array.(Inherited from GenericAcl.)


Returns a new instance of the AceEnumerator class cast as an instance of the IEnumerator interface.(Inherited from GenericAcl.)


Overloaded. Enables parallelization of a query.(Defined by ParallelEnumerable.)


Overloaded. Converts an IEnumerable to an IQueryable.(Defined by Queryable.)


Casts the elements of an IEnumerable to the specified type.(Defined by Enumerable.)


Filters the elements of an IEnumerable based on a specified type.(Defined by Enumerable.)

  • Certain combinations of inheritance and access mask flags are meaningless:

  • Any access control entry (ACE) with a zero-access mask is removed.

  • Inherit-only ACEs inside object ACLs are removed.

  • InheritOnly, NoPropagateInherit, F:System.Security.AccessControl.InheritanceFlags.ContainerInherit, and ObjectInherit flags on all ACEs in leaf object ACLs are cleared.

  • ACEs that have an InheritOnly flag in the absence of the ContainerInherit or ObjectInherit flag are meaningless; they are removed.

  • The NoPropagateInherit flag in the absence of the ContainerInherit or ObjectInherit flag can be removed.

  • ACEs that have an AuditFlags value of F: System.Security.AccessControl.AuditFlags.Success or Failure in discretionary access control lists (DACLs) are removed.

  • Any audit ACE that does not specify either F: System.Security.AccessControl.AuditFlags.Success or Failure is removed.

  • On DACLs, SystemAudit and SystemAlarm ACEs are removed.

  • On system access control lists (SACLs), AccessAllowed and AccessDenied ACEs are removed.

Canonical order is maintained according to the following algorithm:

  • Explicit ACEs take precedence over inherited ACEs; this rule applies to both DACLs and SACLs.

  • In DACLs, among the explicit ACEs, ACEs that deny access take precedence over ACEs that allow access. For directory object ACLs, the nonobject ACEs come before object ACEs.

  • All common ACEs take precedence over noncommon ACEs.

  • Inherited ACEs maintain their relative order after canonicity.

  • Unrecognized and custom ACEs are disallowed in both DACLs and SACLs.

  • Within contiguous ranges (explicit AccessDenied and AccessAllowed ACEs on DACLs, all explicit ACEs on SACLs), the ACEs are sorted by using the M:System.Security.Principal.SecurityIdentifier.CompareTo methods of the SecurityIdentifier objects associated with the ACEs.

Adjacent ACEs are combined, if appropriate. This reduces the size of the ACL without affecting the access control semantics it grants.

.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
© 2015 Microsoft