System.Delegate Class

Summary

Represents a delegate, which is a data structure that refers to a static method or to a class instance and an instance method of that class.

C# Syntax:

[Serializable] public abstract class Delegate : ICloneable, ISerializable

The Delegate class is the base class for delegate types. However, only the system and compilers can derive explicitly from the Delegate class or from the MulticastDelegate class. It is also not permissible to derive a new type from a delegate type. The Delegate class is not considered a delegate type; it is a class used to derive delegate types.

Most languages implement a delegate keyword, and compilers for those languages are able to derive from the MulticastDelegate class; therefore, users should use the delegate keyword provided by the language.

The declaration of a delegate type establishes a contract that specifies the signature of one or more methods. A delegate is an instance of a delegate type, and references one or more of the following:

• A target object that is not null and an instance method of the target object
• A static method

A delegate can reference a method only if the signature of the method exactly matches the signature specified by the delegate type. When a delegate references an instance method, the delegate stores a reference to the method's entry point and a reference to an object, called the target, which is the class instance that the method is invoked on. The target of an instance method cannot be null. When a delegate references a static method, the delegate stores a reference to the method's entry point. The target of a static method is null.

The invocation list of a delegate is an ordered set of delegates in which each element of the list invokes exactly one of the methods invoked by the delegate. An invocation list can contain duplicate methods. During an invocation, a delegate invokes methods in the order in which they appear in the invocation list. A delegate attempts to invoke every method in its invocation list; duplicates are invoked once for each time they appear in the invocation list. Delegates are immutable; once created, the invocation list of a delegate does not change.

A delegate is either multicast (combinable) or singlecast (noncombinable). Multicast or combinable delegates invoke one or more methods, and can be used in combining operations. Singlecast or noncombinable delegates invoke exactly one method and cannot be used in combining operations. The invocation list of a singlecast delegate A contains a single element: a reference to A.

Combining operations, such as Delegate.Combine and Delegate.Remove, do not alter existing delegates. Instead, such an operation returns a new delegate that contains the results of the operation, an unchanged delegate, or null. A combining operation returns null when the result of the operation is a delegate that does not reference at least one method. A combining operation returns an unchanged delegate when the requested operation has no effect.

If an invoked method throws an exception, the method stops executing, the exception is passed back to the caller of the delegate, and remaining methods in the invocation list are not invoked. Catching the exception in the caller does not alter this behavior.

When the signature of the methods invoked by a delegate includes a return value, the delegate returns the return value of the last element in the invocation list. When the signature includes a parameter that is passed by reference, the final value of the parameter is the result of every method in the invocation list executing sequentially and updating the parameter's value.

Compilers provide two additional methods to the delegate: BeginInvoke and EndInvoke. For more information on these methods, see .

The closest equivalent of a delegate in C or C++ is a function pointer. However, a function pointer can only reference static functions, whereas a delegate can reference both static and instance methods. When the delegate references an instance method, the delegate stores not only a reference to the method's entry point, but also a reference to the class instance for which to invoke the method. Unlike function pointers, delegates are object-oriented, type-safe, and secure.

The following example shows how to define a standard delegate.

 using System;
 public class SamplesDelegate  {
 
    // Declares a delegate for a method that takes in an int and returns a String.
    public delegate String myMethodDelegate( int myInt );
 
    // Defines some methods to which the delegate can point.
    public class mySubClass  {
 
       public static String myStringMethod ( int myInt )  {
          if ( myInt > 0 )
             return( "positive" );
          if ( myInt < 0 )
             return( "negative" );
          return ( "zero" );
       }
 
       public static String mySignMethod ( int myInt )  {
          if ( myInt > 0 )
             return( "+" );
          if ( myInt < 0 )
             return( "-" );
          return ( "" );
       }
    }
 
    public static void Main()  {
 
       // Creates one delegate for each method.
       myMethodDelegate myD1 = new myMethodDelegate( mySubClass.myStringMethod );
       myMethodDelegate myD2 = new myMethodDelegate( mySubClass.mySignMethod );
 
       // Invokes the delegates.
       Console.WriteLine( "{0} is {1}; use the sign \"{2}\".\n", 5, myD1( 5 ), myD2( 5 ) );
       Console.WriteLine( "{0} is {1}; use the sign \"{2}\".\n", -3, myD1( -3 ), myD2( -3 ) );
       Console.WriteLine( "{0} is {1}; use the sign \"{2}\".\n", 0, myD1( 0 ), myD2( 0 ) );
    }
 
 }
 /*
 Output:
 
 5 is positive; use the sign "+".
 -3 is negative; use the sign "-".
 0 is zero; use the sign "".
  */ 

    

System Namespace | MulticastDelegate

System.Delegate Member List:

Public Properties

Method	Read-only Gets the static method represented by the delegate.
Target	Read-only Gets the class instance on which the current delegate invokes the instance method.

Public Methods

Clone	Creates a shallow copy of the delegate.
Combine	Overloaded: Combine(Delegate[] delegates) Concatenates the invocation lists of an array of multicast (combinable) delegates.
Combine	Overloaded: Combine(Delegate a, Delegate b) Concatenates the invocation lists of two multicast (combinable) delegates.
CreateDelegate	Overloaded: CreateDelegate(Type type, MethodInfo method) Creates a delegate of the specified type to represent the specified static method.
CreateDelegate	Overloaded: CreateDelegate(Type type, object target, string method) Creates a delegate of the specified type that represents the specified instance method to invoke on the specified class instance.
CreateDelegate	Overloaded: CreateDelegate(Type type, Type target, string method) Creates a delegate of the specified type that represents the specified static method of the specified class.
CreateDelegate	Overloaded: CreateDelegate(Type type, object target, string method, bool ignoreCase) Creates a delegate of the specified type that represents the specified instance method to invoke on the specified class instance with the specified case-sensitivity.
DynamicInvoke	Dynamically invokes (late-bound) the method represented by the current delegate.
Equals	Overridden: Determines whether the specified object and the current singlecast (noncombinable) delegate share the same target, method, and invocation list.
GetHashCode	Overridden: Returns a hash code for the delegate.
GetInvocationList	Returns the invocation list of the delegate.
GetObjectData	Implements the ISerializable interface and returns the data needed to serialize the delegate.
GetType (inherited from System.Object)	See base class member description: System.Object.GetType Derived from System.Object, the primary base class for all objects.
Remove	Removes the invocation list of a delegate from the invocation list of another delegate.
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 the specified delegates are equal.
op_Inequality	Determines whether the specified delegates are not equal.

Protected Constructors

ctor #1	Overloaded: .ctor(object target, string method) Initializes a delegate that invokes the specified instance method on the specified class instance.
ctor #2	Overloaded: .ctor(Type target, string method) Initializes a delegate that invokes the specified static method from the specified class.

Protected Methods

CombineImpl	Concatenates the invocation lists of the specified multicast (combinable) delegate and the current multicast (combinable) delegate.
DynamicInvokeImpl	Dynamically invokes (late-bound) the method represented by the current delegate.
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	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	Removes the invocation list of a delegate from the invocation list of another delegate.

Hierarchy:

• System.Object
• System.Delegate
  • System.MulticastDelegate

System.Delegate Member Details

Summary

Initializes a delegate that invokes the specified instance method on the specified class instance.

C# Syntax:

protected Delegate(    object target,    string method );

target

The class instance on which the delegate invokes method.

method

The name of the instance method that the delegate represents.

Exceptions

Exception Type	Condition
ArgumentNullException	target is null. -or- method is null.

This constructor is called by a compiler-generated delegate type to create a delegate based on the name of an instance method and an instance of the class that defines that method.

This constructor creates delegates for instance methods only. 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.

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Summary

Initializes a delegate that invokes the specified static method from the specified class.

C# Syntax:

protected Delegate(    Type target,    string method );

target

The Type representing the class that defines method.

method

The name of the static method that the delegate represents.

Exceptions

Exception Type	Condition
ArgumentNullException	target is null. -or- method is null.

This constructor is called by a compiler-generated delegate type to create a delegate based on the name of a static method and the Type representing the class that defines that method.

This constructor creates delegates for static methods only. 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.

To get the Type that represents a class, use the Type.GetType method with the fully qualified (including namespace) name of the class. For example, passing "System.Threading.ThreadStart" to Type.GetType returns a Type for the ThreadStart class.

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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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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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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

Concatenates the invocation lists of an array of multicast (combinable) delegates.

C# Syntax:

public static Delegate Combine(    Delegate[] delegates );

delegates

The array of multicast (combinable) delegates to combine.

Return Value:

A new multicast (combinable) delegate with an invocation list that concatenates the invocation lists of the delegates in the delegates array.

-or-

null, if delegates is null, if delegates contains zero elements, or if every entry in delegates is null.

Exceptions

Exception Type	Condition
ArgumentException	Not all the non-null entries in delegates are instances of the same delegate type.
MulticastNotSupportedException	One or more non-null entries in delegates are singlecast (noncombinable) delegates.

If the delegates array contains entries that are null, those entries are ignored.

The invocation list can contain duplicate entries; that is, entries that refer to the same method on the same object.

Delegate.Combine is useful for creating event handlers that call multiple methods each time an event occurs.

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Summary

Concatenates the invocation lists of two multicast (combinable) delegates.

C# Syntax:

public static Delegate Combine(    Delegate a,    Delegate b );

a

The multicast (combinable) delegate whose invocation list comes first.

b

The multicast (combinable) delegate whose invocation list comes last.

Return Value:

A new multicast (combinable) delegate with an invocation list that concatenates the invocation lists of a and b in that order.

-or-

a, if b is null.

-or-

b, if a is null.

-or-

null, if both a and b are null.

Exceptions

Exception Type	Condition
ArgumentException	Both a and b are not null, and a and b are not instances of the same delegate type.
MulticastNotSupportedException	Both a and b are not null and are singlecast (noncombinable) delegates.

The invocation list can contain duplicate entries; that is, entries that refer to the same method on the same object.

Delegate.Combine is useful for creating event handlers that call multiple methods each time an event occurs.

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Summary

Concatenates the invocation lists of the specified multicast (combinable) delegate and the current multicast (combinable) delegate.

C# Syntax:

protected virtual Delegate CombineImpl(    Delegate d );

d

The multicast (combinable) delegate whose invocation list to append to the end of the invocation list of the current multicast (combinable) delegate.

Return Value:

A new multicast (combinable) delegate with an invocation list that concatenates the invocation list of the current multicast (combinable) delegate and the invocation list of d.

-or-

The current multicast (combinable) delegate, if d is null.

Exceptions

Exception Type	Condition
MulticastNotSupportedException	Always thrown.

This method applies only if the current delegate is multicast (combinable).

The current implementation simply throws a MulticastNotSupportedException.

The invocation list can contain duplicate entries; that is, entries that refer to the same method on the same object.

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Summary

Creates a delegate of the specified type to represent the specified static method.

C# Syntax:

public static Delegate CreateDelegate(    Type type,    MethodInfo method );

type

The Type of delegate to create.

method

The MethodInfo describing the static method for which the delegate is to be created.

Return Value:

A delegate of the specified type to represent the specified static method.

Exceptions

Exception Type	Condition
ArgumentNullException	type is null. -or- method is null.
ArgumentException	type does not inherit from either Delegate or MulticastDelegate. -or- method is not a static method.
InvalidProgramException	The Invoke method of type is not found.
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).
SecurityException	method is outside the current assembly and the caller does not have ReflectionPermission for the assembly containing method.

This method creates delegates for static methods only. 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.

To get the Type that represents a class, use the Type.GetType method with the fully qualified (including namespace) name of the class. For example, passing "System.Threading.ThreadStart" to Type.GetType returns a Type for the ThreadStart class.

ReflectionPermissionFlag.MemberAccess for access to the method represented by the delegate.

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Summary

Creates a delegate of the specified type that represents the specified instance method to invoke on the specified class instance.

C# Syntax:

public static Delegate CreateDelegate(    Type type,    object target,    string method );

type

The Type of delegate to create.

target

The class instance on which method is invoked.

method

The name of the instance method that the delegate is to represent.

Return Value:

A delegate of the specified type that represents the specified instance method to invoke on the specified class instance.

Exceptions

Exception Type	Condition
ArgumentNullException	type is null. -or- target is null. -or- method is null.
ArgumentException	type does not inherit from either Delegate or MulticastDelegate. -or- method is not an instance method.
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).
SecurityException	method is outside the current assembly and the caller does not have ReflectionPermission for the assembly containing method.

This method creates delegates for instance methods only. 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.

To get the Type that represents a class, use the Type.GetType method with the fully qualified (including namespace) name of the class. For example, passing "System.Threading.ThreadStart" to Type.GetType returns a Type for the ThreadStart class.

ReflectionPermissionFlag.MemberAccess for access to the method represented by the delegate.

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Summary

Creates a delegate of the specified type that represents the specified static method of the specified class.

C# Syntax:

public static Delegate CreateDelegate(    Type type,    Type target,    string method );

type

The Type of delegate to create.

target

The Type representing the class that implements method. The Type representing the class that implements method.

method

The name of the static method that the delegate is to represent.

Return Value:

A delegate of the specified type that represents the specified static method of the specified class.

Exceptions

Exception Type	Condition
ArgumentNullException	type is null. -or- target is null. -or- method is null.
ArgumentException	type does not inherit from either Delegate or MulticastDelegate. -or- method is not a static method.
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).
SecurityException	method is outside the current assembly and the caller does not have ReflectionPermission for the assembly containing method.

This method creates delegates for static methods only. 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.

To get the Type that represents a class, use the Type.GetType method with the fully qualified (including namespace) name of the class. For example, passing "System.Threading.ThreadStart" to Type.GetType returns a Type for the ThreadStart class.

ReflectionPermissionFlag.MemberAccess for access to the method represented by the delegate.

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Summary

Creates a delegate of the specified type that represents the specified instance method to invoke on the specified class instance with the specified case-sensitivity.

C# Syntax:

public static Delegate CreateDelegate(    Type type,    object target,    string method,    bool ignoreCase );

type

The Type of delegate to create.

target

The class instance on which method is invoked.

method

The name of the instance method that the delegate is to represent.

ignoreCase

A Boolean indicating whether to ignore the case when comparing the name of the method.

Return Value:

A delegate of the specified type that represents the specified instance method to invoke on the specified class instance.

Exceptions

Exception Type	Condition
ArgumentNullException	type is null. -or- target is null. -or- method is null.
ArgumentException	type does not inherit from either Delegate or MulticastDelegate. -or- method is not an instance method.
MemberAccessException	The caller does not have access to the method represented by the delegate (for example, if the method is private).
SecurityException	method is outside the current assembly and the caller does not have ReflectionPermission for the assembly containing method.

This method creates delegates for instance methods only. 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.

To get the Type that represents a class, use the Type.GetType method with the fully qualified (including namespace) name of the class. For example, passing "System.Threading.ThreadStart" to Type.GetType returns a Type for the ThreadStart class.

ReflectionPermissionFlag.MemberAccess for access to the method represented by the delegate.

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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

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

C# Syntax:

protected virtual object DynamicInvokeImpl(    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 implements the Delegate.DynamicInvoke method.

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Summary

Determines whether the specified object and the current singlecast (noncombinable) delegate share the same target, method, and invocation list.

C# Syntax:

public override bool Equals(    object obj );

obj

The object to compare with the current singlecast (noncombinable) delegate.

Return Value:

true if obj and the current delegate have the same target, method, and invocation list; otherwise, false.

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 is singlecast (noncombinable).

Two delegates with the same methods, the same targets, and the same invocation lists are considered equal, even if they are not both multicast (combinable) or both singlecast (noncombinable).

The methods and targets are compared for equality as follows:

• If the two methods being compared are both static and are the same method on the same class, the methods are considered equal and the targets are also considered equal.
• If the two methods being compared are instance methods and are the same method on the same object, the methods are considered equal and the targets are also considered equal.
• Otherwise, the methods are not considered to be equal and the targets are also not considered to be equal.

Two invocation lists are considered identical only if they have the same order and the corresponding elements from the two lists represent the same method and target.

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

C# Syntax:

~Delegate();

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

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Summary

Returns a hash code for the delegate.

C# Syntax:

public override int GetHashCode();

Return Value:

A hash code for the delegate.

The return value of this method must not be persisted for two reasons. First, the hash function of a class might be altered to generate a better distribution, rendering any values from the old hash function useless. Second, the default implementation of this class does not guarantee that the same value will be returned by different instances.

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Summary

Returns the invocation list of the delegate.

C# Syntax:

public virtual Delegate[] GetInvocationList();

Return Value:

An array of singlecast (noncombinable) delegates representing the invocation list of the current delegate. If the current delegate is singlecast (noncombinable), the array contains only one element, which is a reference to the current delegate. If the current delegate is multicast (combinable), the array contains one or more elements.

Because the returned array contains only singlecast (noncombinable) delegates, the invocation list of each element is guaranteed to have exactly one entry.

The order of the delegates in the array is the same order in which the current delegate invokes the methods that those delegates represent.

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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

Implements the ISerializable interface and returns the data needed to serialize the delegate.

C# Syntax:

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

info

A SerializationInfo containing information required to serialize the delegate.

context

A StreamingContext containing the source and destination of the serialized stream associated with the delegate.

Exceptions

Exception Type	Condition
ArgumentNullException	info is null.

Implements:

ISerializable.GetObjectData

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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 the specified delegates are equal.

C# Syntax:

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

d1

The first delegate to compare.

d2

The second delegate to compare.

Return Value:

true if d1 is equal to d2; otherwise, false.

Two delegates with the same methods, the same targets, and the same invocation lists are considered equal, even if they are not both multicast (combinable) or both singlecast (noncombinable).

The methods and targets are compared for equality as follows:

• If the two methods being compared are both static and are the same method on the same class, the methods are considered equal and the targets are also considered equal.
• If the two methods being compared are instance methods and are the same method on the same object, the methods are considered equal and the targets are also considered equal.
• Otherwise, the methods are not considered to be equal and the targets are also not considered to be equal.

Two invocation lists are considered identical if they have the same order and the corresponding elements from the two lists represent the same method and target.

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Summary

Determines whether the specified delegates are not equal.

C# Syntax:

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

d1

The first delegate to compare.

d2

The second delegate to compare.

Return Value:

true if d1 is not equal to d2; otherwise, false.

Two delegates are considered not equal if they have different methods, different targets, or different invocation lists.

The methods and targets are compared for equality as follows:

• If the two methods being compared are both static and are the same method on the same class, the methods are considered equal and the targets are also considered equal.
• If the two methods being compared are instance methods and are the same method on the same object, the methods are considered equal and the targets are also considered equal.
• Otherwise, the methods are not considered to be equal and the targets are also not considered to be equal.

Two invocation lists are not equal if they have different sizes, if they are ordered differently, or if at least one element from one list represents a method or target that is different from that represented by its corresponding element in the other list.

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Summary

Removes the invocation list of a delegate from the invocation list of another delegate.

C# Syntax:

public static Delegate Remove(    Delegate source,    Delegate value );

source

The delegate from which to remove the invocation list of value.

value

The delegate that supplies the invocation list to remove from the invocation list of source.

Return Value:

A new delegate with an invocation list formed by taking the invocation list of source and removing the invocation list of value, if the invocation list of value is found within the invocation list of source.

-or-

source, if value is null, or if the invocation list of value is not found within the invocation list of source.

-or-

null, if the invocation list of value is equal to the invocation list of source, or if source is null.

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).

If the invocation list of value matches a contiguous set of elements in the invocation list of source, then the invocation list of value is said to occur within the invocation list of source. If the invocation list of value occurs more than once in the invocation list of source, the last occurrence is removed.

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Summary

Removes the invocation list of a delegate from the invocation list of another delegate.

C# Syntax:

protected virtual Delegate RemoveImpl(    Delegate d );

d

The delegate that supplies the invocation list to remove from the invocation list of the current delegate.

Return Value:

A new delegate with an invocation list formed by taking the invocation list of the current delegate and removing the invocation list of value, if the invocation list of value is found within the current delegate's invocation list.

-or-

The current delegate, if value is null, or if the invocation list of value is not found within the current delegate's invocation list.

-or-

null, if the invocation list of value is equal to the current delegate's invocation list.

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).

If the invocation list of value matches a contiguous set of elements in the current delegate's invocation list, then the invocation list of value is said to occur within the current delegate's invocation list. If the invocation list of value occurs more than once in the current delegate's invocation list, the last occurrence is removed.

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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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