System.MulticastDelegate Class

Summary

Represents a multicast delegate; that is, a delegate that can have more than one element in its invocation list.

C# Syntax:

[Serializable] public abstract class MulticastDelegate : Delegate

MulticastDelegate is a special class. Compilers and other tools can derive from this class, but you cannot derive from it explicitly. The same is true of the Delegate class.

A MulticastDelegate has a linked list of delegates, called an invocation list, consisting of one or more elements. When a multicast delegate is invoked, the delegates in the invocation list are called synchronously in the order in which they appear. If an error occurs during execution of the list then an exception is thrown.

System Namespace

System.MulticastDelegate Member List:

Public Properties

Method (inherited from System.Delegate)	Read-only See base class member description: System.Delegate.Method Gets the static method represented by the delegate.
Target (inherited from System.Delegate)	Read-only See base class member description: System.Delegate.Target Gets the class instance on which the current delegate invokes the instance method.

Public Methods

Clone (inherited from System.Delegate)	See base class member description: System.Delegate.Clone Creates a shallow copy of the delegate.
DynamicInvoke (inherited from System.Delegate)	See base class member description: System.Delegate.DynamicInvoke Dynamically invokes (late-bound) the method represented by the current delegate.
Equals	Overridden: Determines whether this multicast delegate and the specified object are equal.
GetHashCode	Overridden: Returns the hash code for this instance.
GetInvocationList	Overridden: Returns the invocation list of this multicast delegate, in invocation order.
GetObjectData	Overridden: Populates a SerializationInfo object with all the data needed to serialize this instance.
GetType (inherited from System.Object)	See base class member description: System.Object.GetType Derived from System.Object, the primary base class for all objects.
ToString (inherited from System.Object)	See base class member description: System.Object.ToString Derived from System.Object, the primary base class for all objects.

Public Operators and Type Conversions

op_Equality	Determines whether two MulticastDelegate objects are equal.
op_Inequality	Determines whether two MulticastDelegate objects are not equal.

Protected Constructors

ctor #1	Overloaded: .ctor(object target, string method) Initializes a new instance of the MulticastDelegate class.
ctor #2	Overloaded: .ctor(Type target, string method) Initializes a new instance of the MulticastDelegate class.

Protected Methods

CombineImpl	Overridden: Combines this Delegate with the specified Delegate to form a new delegate.
DynamicInvokeImpl	Overridden: Processes the full invocation list.
Finalize (inherited from System.Object)	See base class member description: System.Object.Finalize Derived from System.Object, the primary base class for all objects.
GetMethodImpl (inherited from System.Delegate)	See base class member description: System.Delegate.GetMethodImpl Gets the static method represented by the current delegate.
MemberwiseClone (inherited from System.Object)	See base class member description: System.Object.MemberwiseClone Derived from System.Object, the primary base class for all objects.
RemoveImpl	Overridden: Removes an element from the invocation list of this MulticastDelegate that is equal to the specified delegate.

Hierarchy:

• System.Object
• System.Delegate
• System.MulticastDelegate
  • System.AssemblyLoadEventHandler
  • System.AsyncCallback
  • System.ComponentModel.CancelEventHandler
  • System.ComponentModel.CollectionChangeEventHandler
  • System.ComponentModel.PropertyChangedEventHandler
  • System.CrossAppDomainDelegate
  • System.EventHandler
  • System.Net.HttpContinueDelegate
  • System.Reflection.MemberFilter
  • System.Reflection.ModuleResolveEventHandler
  • System.Reflection.TypeFilter
  • System.ResolveEventHandler
  • System.Runtime.Remoting.Messaging.HeaderHandler
  • System.Text.RegularExpressions.MatchEvaluator
  • System.Threading.ThreadStart
  • System.Threading.TimerCallback
  • System.Threading.WaitCallback
  • System.Threading.WaitOrTimerCallback
  • System.UnhandledExceptionEventHandler
  • System.Xml.Schema.ValidationEventHandler
  • System.Xml.Serialization.UnreferencedObjectEventHandler
  • System.Xml.Serialization.XmlAttributeEventHandler
  • System.Xml.Serialization.XmlElementEventHandler
  • System.Xml.Serialization.XmlNodeEventHandler
  • System.Xml.XmlNodeChangedEventHandler

System.MulticastDelegate Member Details

Summary

Initializes a new instance of the MulticastDelegate class.

C# Syntax:

protected MulticastDelegate(    object target,    string method );

target

The object on which method is defined.

method

The name of the method for which a delegate is created.

This MulticastDelegate.#ctor constructor is called from the class produced by the compiler-generated code.

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Summary

Initializes a new instance of the MulticastDelegate class.

C# Syntax:

protected MulticastDelegate(    Type target,    string method );

target

The type of object on which method is defined.

method

The name of the static method for which a delegate is created.

This MulticastDelegate.#ctor constructor is called from a class to generate a delegate based on a static method name and the Type of the class that defines the method.

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Inherited
See base class member description: System.Delegate.Method

Summary

Gets the static method represented by the delegate.

C# Syntax:

public MethodInfo Method {get;}

Exceptions

Exception Type	Condition
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).

This property applies only if the current delegate represents a static method.

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Inherited
See base class member description: System.Delegate.Target

Summary

Gets the class instance on which the current delegate invokes the instance method.

C# Syntax:

public object Target {get;}

An instance method is a method that is associated with an instance of a class; a static method is a method that is associated with the class itself.

If the delegate invokes one or more instance methods, this property returns the target of the last instance method in the invocation list.

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Inherited
See base class member description: System.Delegate.Clone

Summary

Creates a shallow copy of the delegate.

C# Syntax:

public virtual object Clone();

Return Value:

A shallow copy of the delegate.

Implements:

ICloneable.Clone

The clone has the same Type, target, method, and invocation list as the original delegate.

A shallow copy creates a new instance of the same type as the original object, and then copies the non-static fields of the original object. If the field is a value type, a bit-by-bit copy of the field is performed. If the field is a reference type, the reference is copied but the referred object is not; therefore, the reference in the original object and the reference in the clone point to the same object. In contrast, a deep copy of an object duplicates everything directly or indirectly referenced by the fields in the object.

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Summary

Combines this Delegate with the specified Delegate to form a new delegate.

C# Syntax:

protected override Delegate CombineImpl(    Delegate follow );

follow

The delegate to combine with this delegate.

Return Value:

A Delegate that is the new root of the MulticastDelegate invocation list.

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Inherited
See base class member description: System.Delegate.DynamicInvoke

Summary

Dynamically invokes (late-bound) the method represented by the current delegate.

C# Syntax:

public object DynamicInvoke(    object[] args );

args

An array of objects that are the arguments to pass to the method represented by the current delegate.

-or-

null, if the method represented by the current delegate does not require arguments.

An array of objects that are the arguments to pass to the method represented by the current delegate.

-or-

null, if the method represented by the current delegate does not require arguments.

Return Value:

The object returned by the method represented by the delegate.

Exceptions

Exception Type	Condition
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private). -or- The number, order, or type of parameters listed in args is invalid.
TargetException	The method represented by the delegate is an instance method and the target object is null. -or- The method represented by the delegate is invoked on an object or a class that does not support it.
TargetInvocationException	One of the encapsulated methods throws an exception.

This method calls the Delegate.DynamicInvokeImpl method.

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Summary

Processes the full invocation list.

C# Syntax:

protected override object DynamicInvokeImpl(    object[] args );

args

The arguments to pass to the encapsulated method.

Return Value:

An array of type Object that contains the return value of the encapsulated method.

Exceptions

Exception Type	Condition
MemberAccessException	There is an attempt to invoke a method to which the caller does not have access (that is, a private method).
ArgumentException	The number, order, or type of parameters is invalid.
TargetException	An encapsulated method is not static, and the target object is null. -or- There is an attempt to invoke a method on an object or class that does not support the method.
TargetInvocationException	One of the encapsulated methods throws an exception.

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Summary

Determines whether this multicast delegate and the specified object are equal.

C# Syntax:

public override bool Equals(    object obj );

obj

The object to compare with this instance.

Return Value:

true if obj and this instance have the same invocation lists; otherwise, false.

Two delegates are equal if they are not null and are of exactly the same type, their invocation lists contain the same number of elements, and every element in the invocation list of the first delegate is equal to the corresponding element in the invocation list of the second delegate.

Two invocation list elements are equal if they invoke the same instance method on the same target instance, or they invoke the same static method.

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Inherited
See base class member description: System.Object.Finalize

C# Syntax:

~MulticastDelegate();

For more information on members inherited from System.Object click on the link above.

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Summary

Returns the hash code for this instance.

C# Syntax:

public override int GetHashCode();

Return Value:

A 32-bit signed integer hash code.

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Summary

Returns the invocation list of this multicast delegate, in invocation order.

C# Syntax:

public override Delegate[] GetInvocationList();

Return Value:

An array of delegates whose invocation lists collectively match the invocation list of this instance.

The array contains a set of delegates, each with an invocation list of one entry. Invoking these delegates sequentially, in the order they appear in the array, produces the same results as invoking the current instance.

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Inherited
See base class member description: System.Delegate.GetMethodImpl

Summary

Gets the static method represented by the current delegate.

C# Syntax:

protected virtual MethodInfo GetMethodImpl();

Return Value:

A MethodInfo describing the static method represented by the current delegate.

Exceptions

Exception Type	Condition
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).

This method applies only if the current delegate represents a static method.

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Summary

Populates a SerializationInfo object with all the data needed to serialize this instance.

C# Syntax:

public override void GetObjectData(    SerializationInfo info,    StreamingContext context );

info

An object that holds all the data needed to serialize or deserialize this instance.

context

(Reserved) The location where serialized data is stored and retrieved.

Exceptions

Exception Type	Condition
ArgumentNullException	info is null.

Implements:

ISerializable.GetObjectData

This method stores all the information in info necessary to serialize this instance.

The context parameter is reserved and is not currently used in the execution of this method.

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Inherited
See base class member description: System.Object.GetType

C# Syntax:

public Type GetType();

For more information on members inherited from System.Object click on the link above.

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Inherited
See base class member description: System.Object.MemberwiseClone

C# Syntax:

protected object MemberwiseClone();

For more information on members inherited from System.Object click on the link above.

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Summary

Determines whether two MulticastDelegate objects are equal.

C# Syntax:

public static bool operator ==(    MulticastDelegate d1,    MulticastDelegate d2 );

d1

The left operand.

d2

The right operand.

Return Value:

true if d1 and d2 have the same invocation lists; otherwise false.

Two delegates are equal if they are not null and are of exactly the same type, their invocation lists contain the same number of elements, and every element in the invocation list of the first delegate is equal to the corresponding element in the invocation list of the second delegate.

Two invocation list elements are equal if they invoke the same instance method on the same target instance, or they invoke the same static method.

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Summary

Determines whether two MulticastDelegate objects are not equal.

C# Syntax:

public static bool operator !=(    MulticastDelegate d1,    MulticastDelegate d2 );

d1

The left operand.

d2

The right operand.

Return Value:

true if d1 and d2 do not have the same invocation lists; otherwise false.

Two delegates are equal if they are not null and are of exactly the same type, their invocation lists contain the same number of elements, and every element in the invocation list of the first delegate is equal to the corresponding element in the invocation list of the second delegate.

Two invocation list elements are equal if they invoke the same instance method on the same target instance, or they invoke the same static method.

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Summary

Removes an element from the invocation list of this MulticastDelegate that is equal to the specified delegate.

C# Syntax:

protected override Delegate RemoveImpl(    Delegate value );

value

The delegate to search for in the invocation list.

Return Value:

If value is found in the invocation list for this instance, then a new Delegate without value in its invocation list; otherwise, this instance with its original invocation list.

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Inherited
See base class member description: System.Object.ToString

C# Syntax:

public virtual string ToString();

For more information on members inherited from System.Object click on the link above.

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