public System.Security.PermissionSet(System.Security.PermissionSet permSet)

Constructs a new instance of the System.Security.PermissionSet class with the values of the specified System.Security.PermissionSet instance.

Parameter permSet: The System.Security.PermissionSet instance with which to initialize the values of the new instance, or null to initialize an empty permission set.

Throws: : permSet is not null and is not an instance of System.Security.PermissionSet.

If permSet is not null , the new instance is initialized with copies of the objects in permSet, not references to those objects. If permSet is null, the new instance contains no permissions. To add a permission to an empty System.Security.PermissionSet , use System.Security.PermissionSet.AddPermission(System.Security.IPermission).

public System.Security.PermissionSet(System.Security.Permissions.PermissionState state)

Constructs a new instance of the System.Security.PermissionSet class with the specified value.

Parameter state: A System.Security.Permissions.PermissionState value. This value is either System.Security.Permissions.PermissionState.None or System.Security.Permissions.PermissionState.Unrestricted , to specify fully restricted or fully unrestricted access.

Throws: : state is not a valid System.Security.Permissions.PermissionState value.

The new instance contains no permissions. To add a permission to the new instance, use System.Security.PermissionSet.AddPermission(System.Security.IPermission).

public virtual System.Security.IPermission AddPermission(System.Security.IPermission perm)

Adds the specified System.Security.IPermission object to the current instance if that permission does not already exist in the current instance.

Parameter perm: The System.Security.IPermission object to add.

Returns: If perm is null, returns null . If a permission of the same type as perm already exists in the current instance, the union of the existing permission and perm is added to the current instance and is returned.

Throws: : perm is not a System.Security.IPermission object.

The System.Security.IPermission is added if perm is not null and a permission of the same type as perm does not already exist in the current instance. Use this method to add permission objects to the current instance.

public virtual System.Void Assert()

Asserts that calling code can access the resources identified by the permissions contained in the current instance through the code that calls this method, even if callers have not been granted permission to access the resource.

Throws: : The asserting code does not have sufficient permission to call this method. -or- This method was called with permissions already asserted for the current stack frame.

This method is the only way to assert multiple permissions at the same time within a frame because only a single assert can be active on a frame at one time; subsequent asserts will result in an exception. As described above. Use this method to insure that all callers can access a set of secured resources.

public virtual System.Security.PermissionSet Copy()

Returns a new System.Security.PermissionSet containing copies of the objects in the current instance.

Returns: A new System.Security.PermissionSet that is value equal to the current instance.

This method creates copies of the permission objects in the current instance, and adds them to the new instance. This method calls the System.Security.PermissionSet constructor that takes a System.Security.PermissionSet argument, and passes the current instance as that parameter. Use this method to create a new System.Security.PermissionSet instance containing permissions that are identical to the permissions contained in the current instance.

public virtual System.Void CopyTo(System.Array array, System.Int32 index)

Copies the permission objects in the current instance to the specified location in the specified System.Array .

Parameter array: The destination System.Array .

Parameter index: A System.Int32 that specifies the zero-based starting position in the array at which to begin copying.

Throws: : array has more than one dimension.

Throws: : index is outside the range of allowable values for array.

Throws: : array is null.

This method is implemented to support the System.Collections.ICollection interface. As described above. The default implementation uses the System.Array.SetValue(System.Object,System.Int32)(System.Object, System.Int32) method to add the value to the array. Override this method to customize the manner in which elements are added to array .

public virtual System.Void Demand()

Forces a System.Security.SecurityException if all callers do not have the permissions specified by the objects contained in the current instance.

Throws: : A caller does not have the permission specified by the current instance.

The permission check for System.Security.PermissionSet.Demand begins with the immediate caller of the code that calls this method and continues until all callers have been checked or a caller has been found that is not granted the demanded permission, in which case a System.Security.SecurityException exception is thrown. If the current instance is empty, a call to System.Security.PermissionSet.Demand succeeds. Use this method to ensure in a single operation that all callers have all permissions contained in a permission set.

public virtual System.Void Deny()

Denies access to the resources secured by the objects contained in the current instance through the code that calls this method.

Throws: : A previous call to Deny has already restricted the permissions for the current stack frame.

This is the only way to deny multiple permissions at the same time within a frame because only a single deny can be active on a frame at one time; subsequent denies will result in an exception. This method is required to prevent callers from accessing all resources protected by the objects in the current instance even if the callers had been granted permission to access them. A call to System.Security.PermissionSet.Deny is effective until the calling code returns. Use this method to force all security checks for the objects contained in the current instance to fail.

public virtual System.Void FromXml(System.Security.SecurityElement et)

Reconstructs the state of a System.Security.PermissionSet object using the specified XML encoding.

Parameter et: A System.Security.SecurityElement instance containing the XML encoding to use to reconstruct the state of a System.Security.PermissionSet object.

Throws: : et is null.

Throws: : et does not contain an XML encoding for a System.Security.PermissionSet instance. An error occurred while reconstructing et .

For the XML encoding for this class, see the System.Security.PermissionSet class page. When this call completes, the objects in the current instance are required to be identical to the objects in the System.Security.PermissionSet encoded in et . Override this method to reconstruct subclasses of System.Security.PermissionSet . Applications do not typically call this method; it is called by the system.

public virtual System.Collections.IEnumerator GetEnumerator()

Returns an enumerator used to iterate over the permissions in the current instance.

Returns: A System.Collections.IEnumerator object for the permissions of the set.

This method is implemented to support the System.Collections.ICollection interface, which supports the System.Collections.IEnumerable interface. As described above. Override this method to customize the enumerator returned by this method.

public virtual System.Boolean IsSubsetOf(System.Security.PermissionSet target)

Determines whether the current instance is a subset of the specified object.

Parameter target: A System.Security.PermissionSet instance that is to be tested for the subset relationship.

Returns: true if the current instance is a subset of target; otherwise, false. If the current instance is unrestricted, and target is not, returns false. If target is unrestricted, returns true .

The current instance is a subset target if all demands that succeed for the current instance also succeed for target. That is, the current instance is a subset of target if target contains at least the permissions contained in the current instance. If this method returns true , the current instance does not describe a level of access to a set of resources that is not already described by target. As described above. Use this method to determine if the all permissions contained in the current instance are also contained in target.

public virtual System.Void PermitOnly()

Specifies that only the resources described by the current instance can be accessed by calling code, even if the code has been granted permission to access other resources.

Throws: : A previous call to PermitOnly has already set the permissions for the current stack frame.

System.Security.PermissionSet.PermitOnly is similar to System.Security.PermissionSet.Deny in that both methods cause access to fail where it might otherwise succeed. The difference is that System.Security.PermissionSet.Deny specifies permissions for which to refuse access, while System.Security.PermissionSet.PermitOnly specifies the only permissions that will succeed. This is the only way to permit multiple permissions at the same time within a stack frame because only a single permit at a time can be active on a frame; subsequent permits will result in an exception. Callers are required to be prevented from accessing resources not secured by the contents of the current instance, even if a caller has been granted permission to access such resources. A System.Security.PermissionSet.PermitOnly is in effect until the calling code returns to its caller. Use this method to limit access to a specified set of resources.

public System.String ToString()

Returns a System.String representation of the state of the current instance.

Returns: A System.String containing the XML representation of the state of the current instance.

This method overrides System.Object.ToString.

using System;
using System.Security;
using System.Security.Permissions;

public class PermissionSetToStringExample {
  public static void Main() {

    PermissionSet ps = new PermissionSet(PermissionState.Unrestricted);
    Console.WriteLine(ps.ToString());
  }
}

			

public virtual System.Security.SecurityElement ToXml()

Returns the XML encoding of the current instance.

Returns: A System.Security.SecurityElement containing an XML encoding of the state of the current instance.

As described above. Override this method to return an object containing the XML encoding for types derived from System.Security.PermissionSet. This method is called by the system.

public virtual System.Security.PermissionSet Union(System.Security.PermissionSet other)

Returns a System.Security.PermissionSet object that is the union of the current instance and the specified object.

Parameter other: A System.Security.PermissionSet instance to be combined with the current instance.

Returns: A new System.Security.PermissionSet instance that represents the union of the current instance and other. If the current instance or other is unrestricted, returns a System.Security.PermissionSet instance that is unrestricted.

The result of a call to System.Security.PermissionSet.Union(System.Security.PermissionSet) is a new System.Security.PermissionSet instance that represents all the operations represented by the current instance as well as all the operations represented by other . If either set is unrestricted, the union is unrestricted, as well. As described above. Use this method to create a System.Security.PermissionSet instance that contains all of the permissions of the current instance and other .

public virtual System.Boolean Equals(System.Object obj)

Determines whether the specified System.Object is equal to the current instance.

Parameter obj: The System.Object to compare with the current instance.

Returns: true if obj is equal to the current instance; otherwise, false.

The statements listed below are required to be true for all implementations of the System.Object.Equals(System.Object) method. In the list, x, y, and z represent non-null object references. See System.Object.GetHashCode for additional required behaviors pertaining to the System.Object.Equals(System.Object) method. Implementations of System.Object.Equals(System.Object) should not throw exceptions. The System.Object.Equals(System.Object) method tests for referential equality , which means that System.Object.Equals(System.Object) returns true if the specified instance of Object and the current instance are the same instance; otherwise, it returns false . An implementation of the System.Object.Equals(System.Object) method is shown in the following C# code: public virtual bool Equals(Object obj) { return this == obj; } For some kinds of objects, it is desirable to have System.Object.Equals(System.Object) test for value equality instead of referential equality. Such implementations of Equals return true if the two objects have the same "value", even if they are not the same instance. The definition of what constitutes an object's "value" is up to the implementer of the type, but it is typically some or all of the data stored in the instance variables of the object. For example, the value of a System.String is based on the characters of the string; the Equals method of the System.String class returns true for any two string instances that contain exactly the same characters in the same order. When the Equals method of a base class provides value equality, an override of Equals in a class derived from that base class should invoke the inherited implementation of Equals . It is recommended (but not required) that types overriding System.Object.Equals(System.Object) also override System.Object.GetHashCode. Hashtables cannot be relied on to work correctly if this recommendation is not followed. If your programming language supports operator overloading, and if you choose to overload the equality operator for a given type, that type should override the Equals method. Such implementations of the Equals method should return the same results as the equality operator. Following this guideline will help ensure that class library code using Equals (such as System.Collections.ArrayList and System.Collections.Hashtable ) behaves in a manner that is consistent with the way the equality operator is used by application code. If you are implementing a value type, you should follow these guidelines: For reference types, the guidelines are as follows: If you implement System.IComparable on a given type, you should override Equals on that type. The System.Object.Equals(System.Object) method is called by methods in collections classes that perform search operations, including the System.Array.IndexOf(System.Array,System.Object) method and the System.Collections.ArrayList.Contains(System.Object) method.

using System;
class MyClass {
   static void Main() {
      Object obj1 = new Object();
      Object obj2 = new Object();
      Console.WriteLine(obj1.Equals(obj2));
      obj1 = obj2; 
      Console.WriteLine(obj1.Equals(obj2)); 
   }
}

using System;
public class Point: object {
 int x, y;
 public override bool Equals(Object obj) {
 //Check for null and compare run-time types.
 if (obj == null || GetType() != obj.GetType()) return false;
 Point p = (Point)obj;
 return (x == p.x) && (y == p.y);
 }
 public override int GetHashCode() {
 return x ^ y;
 }
}

class Point3D: Point {
 int z;
 public override bool Equals(Object obj) {
 return base.Equals(obj) && z == ((Point3D)obj).z;
 }
 public override int GetHashCode() {
 return base.GetHashCode() ^ z;
 }
}

using System;
class Rectangle {
 Point a, b;
 public override bool Equals(Object obj) {
 if (obj == null || GetType() != obj.GetType()) return false;
 Rectangle r = (Rectangle)obj;
 //Use Equals to compare instance variables
 return a.Equals(r.a) && b.Equals(r.b);
 }
 public override int GetHashCode() {
 return a.GetHashCode() ^ b.GetHashCode();
 }
}

using System;
public struct Complex {
 double re, im;
 public override bool Equals(Object obj) {
 return obj is Complex && this == (Complex)obj;
 }
 public override int GetHashCode() {
 return re.GetHashCode() ^ im.GetHashCode();
 }
 public static bool operator ==(Complex x, Complex y) {
 return x.re == y.re && x.im == y.im;
 }
 public static bool operator !=(Complex x, Complex y) {
 return !(x == y);
 }
}

public static System.Boolean Equals(System.Object objA, System.Object objB)

Determines whether two object references are equal.

Parameter objA: First object to compare.

Parameter objB: Second object to compare.

Returns: true if one or more of the following statements is true: otherwise returns false.

This static method checks for null references before it calls objA.Equals(objB ) and returns false if either objA or objB is null. If the Equals(object obj) implementation throws an exception, this method throws an exception.

using System;

public class MyClass {
   public static void Main() {
   string s1 = "Tom";
   string s2 = "Carol";
   Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", 
      s1, s2, Object.Equals(s1, s2));

   s1 = "Tom";
   s2 = "Tom";
   Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", 
      s1, s2, Object.Equals(s1, s2));

   s1 = null;
   s2 = "Tom";
   Console.WriteLine("Object.Equals(null, \"{1}\") => {2}",
       s1, s2, Object.Equals(s1, s2));

   s1 = "Carol";
   s2 = null;
   Console.WriteLine("Object.Equals(\"{0}\", null) => {2}", 
       s1, s2, Object.Equals(s1, s2));

   s1 = null;
   s2 = null;
   Console.WriteLine("Object.Equals(null, null) => {2}", 
       s1, s2, Object.Equals(s1, s2));
   }
}
   

public System.Void Finalize()

Allows a System.Object to perform cleanup operations before the memory allocated for the System.Object is automatically reclaimed.

During execution, System.Object.Finalize is automatically called after an object becomes inaccessible, unless the object has been exempted from finalization by a call to System.GC.SuppressFinalize(System.Object). During shutdown of an application domain, System.Object.Finalize is automatically called on objects that are not exempt from finalization, even those that are still accessible. System.Object.Finalize is automatically called only once on a given instance, unless the object is re-registered using a mechanism such as System.GC.ReRegisterForFinalize(System.Object) and System.GC.SuppressFinalize(System.Object) has not been subsequently called. Conforming implementations of the CLI are required to make every effort to ensure that for every object that has not been exempted from finalization, the System.Object.Finalize method is called after the object becomes inaccessible. However, there may be some circumstances under which Finalize is not called. Conforming CLI implementations are required to explicitly specify the conditions under which Finalize is not guaranteed to be called. For example, Finalize might not be guaranteed to be called in the event of equipment failure, power failure, or other catastrophic system failures. In addition to System.GC.ReRegisterForFinalize(System.Object) and System.GC.SuppressFinalize(System.Object), conforming implementations of the CLI are allowed to provide other mechanisms that affect the behavior of System.Object.Finalize . Any mechanisms provided are required to be specified by the CLI implementation. The order in which the Finalize methods of two objects are run is unspecified, even if one object refers to the other. The thread on which Finalize is run is unspecified. Every implementation of System.Object.Finalize in a derived type is required to call its base type's implementation of Finalize . This is the only case in which application code calls System.Object.Finalize . The System.Object.Finalize implementation does nothing. A type should implement Finalize when it uses unmanaged resources such as file handles or database connections that must be released when the managed object that uses them is reclaimed. Because Finalize methods may be invoked in any order (including from multiple threads), synchronization may be necessary if the Finalize method may interact with other objects, whether accessible or not. Furthermore, since the order in which Finalize is called is unspecified, implementers of Finalize (or of destructors implemented through overriding Finalize) must take care to correctly handle references to other objects, as their Finalize method may already have been invoked. In general, referenced objects should not be considered valid during finalization. See the System.IDisposable interface for an alternate means of disposing of resources. For C# developers: Destructors are the C# mechanism for performing cleanup operations. Destructors provide appropriate safeguards, such as automatically calling the base type's destructor. In C# code, System.Object.Finalize cannot be called or overridden.

public virtual System.Int32 GetHashCode()

Generates a hash code for the current instance.

Returns: A System.Int32 containing the hash code for the current instance.

System.Object.GetHashCode serves as a hash function for a specific type. A hash function is used to quickly generate a number (a hash code) corresponding to the value of an object. Hash functions are used with hashtables. A good hash function algorithm rarely generates hash codes that collide. For more information about hash functions, see The Art of Computer Programming , Vol. 3, by Donald E. Knuth. All implementations of System.Object.GetHashCode are required to ensure that for any two object references x and y, if x.Equals(y) == true, then x.GetHashCode() == y.GetHashCode(). Hash codes generated by System.Object.GetHashCode need not be unique. Implementations of System.Object.GetHashCode are not permitted to throw exceptions. The System.Object.GetHashCode implementation attempts to produce a unique hash code for every object, but the hash codes generated by this method are not guaranteed to be unique. Therefore, System.Object.GetHashCode may generate the same hash code for two different instances. It is recommended (but not required) that types overriding System.Object.GetHashCode also override System.Object.Equals(System.Object) . Hashtables cannot be relied on to work correctly if this recommendation is not followed. Use this method to obtain the hash code of an object. Hash codes should not be persisted (i.e. in a database or file) as they are allowed to change from run to run.

using System;
public struct Int32 {
 int value;
 //other methods...

 public override int GetHashCode() {
 return value;
 }
}

using System;
public struct Point {
 int x;
 int y; 
 //other methods
 
 public override int GetHashCode() {
 return x ^ y;
 }
}

using System;
public class SomeType {
 public override int GetHashCode() {
 return 0;
 }
}

public class AnotherType {
 public override int GetHashCode() {
 return 1;
 }
}

public class LastType {
 public override int GetHashCode() {
 return 2;
 }
}
public class MyClass {
 SomeType a = new SomeType();
 AnotherType b = new AnotherType();
 LastType c = new LastType();

 public override int GetHashCode () {
 return a.GetHashCode() ^ b.GetHashCode() ^ c.GetHashCode();
 }
}

using System;
public struct Int64 {
 long value;
 //other methods...

 public override int GetHashCode() {
 return ((int)value ^ (int)(value >> 32));
 }
}

public System.Type GetType()

Gets the type of the current instance.

Returns: The instance of System.Type that represents the run-time type (the exact type) of the current instance.

For two objects x and y that have identical run-time types, System.Object.ReferenceEquals(System.Object,System.Object)(x.GetType(),y.GetType()) returns true .

using System;
public class MyBaseClass: Object {
}
public class MyDerivedClass: MyBaseClass {
}
public class Test {
   public static void Main() {
   MyBaseClass myBase = new MyBaseClass();
   MyDerivedClass myDerived = new MyDerivedClass();

   object o = myDerived;
   MyBaseClass b = myDerived;

   Console.WriteLine("mybase: Type is {0}", myBase.GetType());
   Console.WriteLine("myDerived: Type is {0}", myDerived.GetType());
   Console.WriteLine("object o = myDerived: Type is {0}", o.GetType());
   Console.WriteLine("MyBaseClass b = myDerived: Type is {0}", b.GetType());
   }
}

protected System.Object MemberwiseClone()

Creates a shallow copy of the current instance.

Returns: A shallow copy of the current instance. The run-time type (the exact type) of the returned object is the same as the run-time type of the object that was copied.

System.Object.MemberwiseClone creates a new instance of the same type as the current instance and then copies each of the object's non-static fields in a manner that depends on whether the field is a value type or a reference type. If the field is a value type, a bit-by-bit copy of all the field's bits is performed. If the field is a reference type, only the reference is copied. The algorithm for performing a shallow copy is as follows (in pseudo-code): for each instance field f in this instance if (f is a value type) bitwise copy the field if (f is a reference type) copy the reference end for loop This mechanism is referred to as a shallow copy because it copies rather than clones the non-static fields. Because System.Object.MemberwiseClone implements the above algorithm, for any object, a, the following statements are required to be true: System.Object.MemberwiseClone does not call any of the type's constructors. If System.Object.Equals(System.Object) has been overridden, a.MemberwiseClone().Equals(a) might return false . For an alternate copying mechanism, see System.ICloneable . System.Object.MemberwiseClone is protected (rather than public) to ensure that from verifiable code it is only possible to clone objects of the same class as the one performing the operation (or one of its subclasses). Although cloning an object does not directly open security holes, it does allow an object to be created without running any of its constructors. Since these constructors may establish important invariants, objects created by cloning may not have these invariants established, and this may lead to incorrect program behavior. For example, a constructor might add the new object to a linked list of all objects of this class, and cloning the object would not add the new object to that list -- thus operations that relied on the list to locate all instances would fail to notice the cloned object. By making the method protected, only objects of the same class (or a subclass) can produce a clone and implementers of those classes are (presumably) aware of the appropriate invariants and can arrange for them to be true without necessarily calling a constructor.

using System;
class MyBaseClass {
   public static string CompanyName = "My Company";
   public int age;
   public string name;
}

class MyDerivedClass: MyBaseClass {

   static void Main() {
   
   //Create an instance of MyDerivedClass
   //and assign values to its fields.
   MyDerivedClass m1 = new MyDerivedClass();
   m1.age = 42;
   m1.name = "Sam";

   //Do a shallow copy of m1
   //and assign it to m2.
   MyDerivedClass m2 = (MyDerivedClass) m1.MemberwiseClone();
   }
}

+---------------+

|     42        |                           m1 

+---------------+

|     +---------|-----------------> "Sam" 

+---------------+                    /|\ 

                                      | 

+---------------+                     | 

|     42        |                     |      m2 

+---------------+                     | 

|      +--------|---------------------| 

+---------------+

public static System.Boolean ReferenceEquals(System.Object objA, System.Object objB)

Determines whether two object references are identical.

Parameter objA: First object to compare.

Parameter objB: Second object to compare.

Returns: True if a and b refer to the same object or are both null references; otherwise, false.

This static method provides a way to compare two objects for reference equality. It does not call any user-defined code, including overrides of System.Object.Equals(System.Object) .

using System;
class MyClass {
   static void Main() {
   object o = null;
   object p = null;
   object q = new Object();
   Console.WriteLine(Object.ReferenceEquals(o, p));
   p = q;
   Console.WriteLine(Object.ReferenceEquals(p, q));
   Console.WriteLine(Object.ReferenceEquals(o, p));
   }
}
   

public virtual System.String ToString()

Creates and returns a System.String representation of the current instance.

Returns: A System.String representation of the current instance.

System.Object.ToString returns a string whose content is intended to be understood by humans. Where the object contains culture-sensitive data, the string representation returned by System.Object.ToString takes into account the current system culture. For example, for an instance of the System.Double class whose value is zero, the implementation of System.Double.ToString might return "0.00" or "0,00" depending on the current UI culture. Although there are no exact requirements for the format of the returned string, it should as much as possible reflect the value of the object as perceived by the user. System.Object.ToString is equivalent to calling System.Object.GetType to obtain the System.Type object for the current instance and then returning the result of calling the System.Object.ToString implementation for that type. The value returned includes the full name of the type. It is recommended, but not required, that System.Object.ToString be overridden in a derived class to return values that are meaningful for that type. For example, the base data types, such as System.Int32, implement System.Object.ToString so that it returns the string form of the value the object represents. Subclasses that require more control over the formatting of strings than System.Object.ToString provides should implement System.IFormattable, whose System.Object.ToString method uses the culture of the current thread.

using System;

class MyClass {
   static void Main() {
      object o = new object();
      Console.WriteLine (o.ToString());
   }
}
      

public System.Void CopyTo(System.Array array, System.Int32 index)

Copies the elements from the current instance to the specified System.Array, starting at the specified index in the array.

Parameter array: A one-dimensional, zero-based System.Array that is the destination of the elements copied from the current instance.

Parameter index: A System.Int32 that specifies the zero-based index in array at which copying begins.

Throws: : array is null.

Throws: : index < 0.

Throws: : array has more than one dimension. index is greater than or equal to array.Length. The sum of index and the System.Collections.ICollection.Count of the current instance is greater than array.Length.

Throws: : At least one element in the current instance is not assignment-compatible with the type of array.

As described above. Use this method to copy from a collection to a System.Array.

public System.Collections.IEnumerator GetEnumerator()

Returns a System.Collections.IEnumerator that can be used for simple iteration over a collection.

Returns: A System.Collections.IEnumerator that can be used for simple iteration over a collection.

As described above. For a detailed description regarding the use of an enumerator, see System.Collections.IEnumerator.

public System.Collections.IEnumerator GetEnumerator()

Returns a System.Collections.IEnumerator that can be used for simple iteration over a collection.

Returns: A System.Collections.IEnumerator that can be used for simple iteration over a collection.

As described above. For a detailed description regarding the use of an enumerator, see System.Collections.IEnumerator.