Is Delegate Can Be Implemented?

What is a delegate method?

A delegate method is a method that the delegate object is expected to implement.

Some delegate methods are required, while some are not.

In IOS, most delegates are expected to conform to an Objective-C protocol; the protocol declaration will tell you which methods are optional and which are required..

What do delegates do C#?

A delegate is a type that represents references to methods with a particular parameter list and return type. When you instantiate a delegate, you can associate its instance with any method with a compatible signature and return type. You can invoke (or call) the method through the delegate instance.

What do you mean by delegates state their use with an example?

A delegate is an object which refers to a method or you can say it is a reference type variable that can hold a reference to the methods. Delegates in C# are similar to the function pointer in C/C++. … For example, if you click an Button on a form (Windows Form application), the program would call a specific method.

What is the difference between lambdas and delegates?

A lambda-expression is a form of anonymous function. A delegate is a Queue of function pointers, invoking a delegate may invoke multiple methods. … The difference really is that a lambda is a terse way to define a method inside of another expression, while a delegate is an actual object type.

What is the difference between func string string and delegate?

Func is a generic delegate included in the System namespace. It has zero or more input parameters and one out parameter. … This delegate can point to a method that takes up to 16 Parameters and returns a value. Below is the Func delegate with two input and an output parameter.

What is C# delegate?

C# delegates are similar to pointers to functions, in C or C++. A delegate is a reference type variable that holds the reference to a method. The reference can be changed at runtime. Delegates are especially used for implementing events and the call-back methods. All delegates are implicitly derived from the System.

Why delegates why not call methods directly?

But you question here why we use the delegate instead of calling the method directly? So, the simple answer that, It is used for designing extensible and flexible application ( or design the framework). You can point any methods in the application through the delegate instance,which match the signature of the delegate.

Can we declare delegate inside interface and why?

An interface contains only the signatures of methods, delegates or events. However, in the remarks on the same page it says that an interface can contain signatures of methods, properties, indexers and events. If you try to put a delegate in an interface, the compiler says that “interfaces cannot declare types.”

What is the point of delegates?

The primary purpose of delegates is to vote on a party’s candidate for primary and general elections.

Which statement is true of delegates?

Delegates are reference types. Delegates are object oriented. Delegates are type-safe. Delegates serve the same purpose as function pointers in C and pointers to member function operators in C++.

What means interface?

1a : the place at which independent and often unrelated systems meet and act on or communicate with each other the man-machine interface. b : the means by which interaction or communication is achieved at an interface. 2 : a surface forming a common boundary of two bodies, spaces, or phases an oil-water interface.

Is it necessary to use delegates?

Delegates are similar to C++ function pointers, but are type safe. Delegates allow methods to be passed as parameters. Delegates can be used to define callback methods. … Methods don’t need to match the delegate signature exactly.

What is difference between delegate and method?

A delegate is a method with a parameter and a return type. A delegate is a type that safely encapsulates a method. Delegates are object-oriented, type safe, and secure.

What is callback delegate in C#?

It is basically a function pointer that is being passed into another function. Delegate is a famous way to implement Callback in C#. … Delegate provides a way to pass a method as argument to other method. To create a Callback in C#, function address will be passed inside a variable.

Can delegates be private C#?

Just like classes and interfaces, we can declare delegates outside of classes or nested within classes. We can mark them private , public , or internal .

What is difference between delegate and interface in C#?

A Delegate is an object which refers to a method or you can say it is a reference type variable that can hold a reference to the methods. Delegates in C# are similar to the function pointer in C/C++….Related Articles.DelegateInterfaceIt could be a method only.It contains both methods and properties.11 more rows•Apr 17, 2019

What is difference between events and delegates?

Delegate is a function pointer. It holds the reference of one or more methods at runtime. Delegate is independent and not dependent on events. An event is dependent on a delegate and cannot be created without delegates.

How are delegates counted?

The Democratic Party uses a proportional representation to determine how many delegates each candidate is awarded in each state. A candidate must win at least 15% of the vote in a particular contest in order to receive any delegates. Pledged delegates are awarded proportionally in both state-wide and regional contests.

How do I invoke a delegate?

Delegates can be invoke like a normal function or Invoke() method. Multiple methods can be assigned to the delegate using “+” or “+=” operator and removed using “-” or “-=” operator. It is called multicast delegate. If a multicast delegate returns a value then it returns the value from the last assigned target method.

When would you use delegates instead of interfaces?

When should Delegate be used in place of InterfaceIf Interface defines only a single method then we should use Delegate.If multicast is required.If subscriber need to implement the interface multiple times.Oct 28, 2015

What are events in csharp?

C# – EventsEvents are user actions such as key press, clicks, mouse movements, etc., or some occurrence such as system generated notifications. … The events are declared and raised in a class and associated with the event handlers using delegates within the same class or some other class.More items…

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