Oid Class


Represents a cryptographic object identifier. This class cannot be inherited.

Namespace:   System.Security.Cryptography
Assembly:  System (in System.dll)


public ref class Oid sealed 


Initializes a new instance of the Oid class.


Initializes a new instance of the Oid class using the specified Oid object.


Initializes a new instance of the Oid class using a string value of an Oid object.

System_CAPS_pubmethodOid(String^, String^)

Initializes a new instance of the Oid class using the specified value and friendly name.


Gets or sets the friendly name of the identifier.


Gets or sets the dotted number of the identifier.


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

System_CAPS_pubmethodSystem_CAPS_staticFromFriendlyName(String^, OidGroup)

Creates an Oid object from an OID friendly name by searching the specified group.

System_CAPS_pubmethodSystem_CAPS_staticFromOidValue(String^, OidGroup)

Creates an Oid object by using the specified OID value and group.


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


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


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

Cryptographic object identifiers consist of a value/name pair. If one property in a pair is set to a known value, the other property is updated automatically to a corresponding value. For example, if the Value property is set to "", the FriendlyName property, which is localized, is set automatically to "Secure Email".

The following code example shows how to use the Oid class.

#using <system.dll>

using namespace System;
using namespace System::Security::Cryptography;
int main()

   // Assign values to strings.
   String^ Value1 = "1.2.840.113549.1.1.1";
   String^ Name1 = "3DES";
   String^ Value2 = "";
   String^ InvalidName = "This name is not a valid name";
   String^ InvalidValue = "";

   // Create new Oid objects using the specified values.
   // Note that the corresponding Value or Friendly Name property is automatically added to the object.
   Oid ^ o1 = gcnew Oid( Value1 );
   Oid ^ o2 = gcnew Oid( Name1 );

   // Create a new Oid object using the specified Value and Friendly Name properties.
   // Note that the two are not compared to determine if the Value is associated 
   //  with the Friendly Name.
   Oid ^ o3 = gcnew Oid( Value2,InvalidName );

   //Create a new Oid object using the specified Value. Note that if the value
   //  is invalid or not known, no value is assigned to the Friendly Name property.
   Oid ^ o4 = gcnew Oid( InvalidValue );

   //Write out the property information of the Oid objects.
   Console::WriteLine( "Oid1: Automatically assigned Friendly Name: {0}, {1}", o1->FriendlyName, o1->Value );
   Console::WriteLine( "Oid2: Automatically assigned Value: {0}, {1}", o2->FriendlyName, o2->Value );
   Console::WriteLine( "Oid3: Name and Value not compared: {0}, {1}", o3->FriendlyName, o3->Value );
   Console::WriteLine( "Oid4: Invalid Value used: {0}, {1} {2}", o4->FriendlyName, o4->Value, Environment::NewLine );

   //Create an Oid collection and add several Oid objects.
   OidCollection ^ oc = gcnew OidCollection;
   oc->Add( o1 );
   oc->Add( o2 );
   oc->Add( o3 );
   Console::WriteLine( "Number of Oids in the collection: {0}", oc->Count );
   Console::WriteLine( "Is synchronized: {0} {1}", oc->IsSynchronized, Environment::NewLine );

   //Create an enumerator for moving through the collection.
   OidEnumerator ^ oe = oc->GetEnumerator();

   //You must execute a MoveNext() to get to the first item in the collection.

   // Write out Oids in the collection.
   Console::WriteLine( "First Oid in collection: {0},{1}", oe->Current->FriendlyName, oe->Current->Value );
   Console::WriteLine( "Second Oid in collection: {0},{1}", oe->Current->FriendlyName, oe->Current->Value );

   //Return index in the collection to the beginning.

.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.

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