What’s an abstract class?

What’s an abstract class? 
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1 Answer

Answer :

A class that cannot be instantiated. A concept in C++ known as pure virtual method. A class that must be inherited and have the methods over-ridden. Essentially, it’s a blueprint for a class without any implementation.
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Related questions

What’s the difference between an interface and abstract class?

Description : What’s the difference between an interface and abstract class?

Last Answer : Answer: An abstract class and Interface both have method only but not have body of method.The difference between Abstract class and An Interface is that if u call Ablstract class then u have to call ... type, Parameter type, Parameter Number all must be same . Only body of method can change. 

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Description : What’s an abstract class?

Last Answer : Answer:Classes that cannot be instantiated. We cannot create an object from such a class for use in our program. We can use an abstract class as a base class, creating new classes that will inherit from ... can inherit from a non-abstract class. In C++, this concept is known as pure virtual method.

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Description : What’s an abstract class?

Last Answer : A class that cannot be instantiated. An abstract class is a class that must be inherited and have the methods overridden. An abstract class is essentially a blueprint for a class without any implementation.

Describe an abstract class and explain when one might be useful.

Description : Describe an abstract class and explain when one might be useful.

Last Answer : An abstract class is a class that cannot be instantiated but must be inherited. It can contain both implemented methods and abstract methods, which must be implemented in an inheriting class. ... common interface for other methods, and leave more detailed implementation up to the inheriting class.

When do you absolutely have to declare a class as abstract?

Description : When do you absolutely have to declare a class as abstract?

Last Answer : 1. When the class itself is inherited from an abstract class, but not all base abstract methods have been overridden. 2. When at least one of the methods in the class is abstract.

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Description : When do you absolutely have to declare a class as abstract?

Last Answer : 1. When the class itself is inherited from an abstract class, but not all base abstract methods have been overridden. 2. When at least one of the methods in the class is abstract.

When do you absolutely have to declare a class as abstract (as opposed to free-willed educated choice or decision based on UML diagram)?

Description : When do you absolutely have to declare a class as abstract (as opposed to free-willed educated choice or decision based on UML diagram)?

Last Answer : When at least one of the methods in the class is abstract. When the class itself is inherited from an abstract class, but not all base abstract methods have been overridden.

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Description : Define what are the features of abstract class?

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Description : Can abstract methods override virtual methods? 

Last Answer : Yes

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Description : What’s the .NET collection class that allows an element to be accessed using a unique key?

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Last Answer : System.Object.

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Description : What’s an interface class? 

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What’s the implicit name of the parameter that gets passed into the class’ set method?

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Description : Do you need to instantiate a class before accessing a Shared (static) member? Why or why not?

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Description : How do you enable your application to use .NET base class library members without referencing their fully qualified names?

Last Answer : Use the Imports keyword (Visual Basic .NET) or the using keyword (Visual C#) to make a .NET Framework namespace visible to your application. 

what is Class ?

Description : what is Class ?

Last Answer : Answer:A group of objects that share a common definition and that therefore share common properties, operations, and behavior. A user-defined type that is defined with the class-key 'class,' 'struct, ... one class to be an expansion of another, and classes can restrict access to their members. 

How do you specify a custom attribute for the entire assembly (rather than for a class) ?

Description : How do you specify a custom attribute for the entire assembly (rather than for a class) ?

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Description : If a base class has a number of overloaded constructors, and an inheriting class has a number of overloaded constructors; can you enforce a call from an inherited constructor to a specific base constructor?

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What is the difference between a Struct and a Class?

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Last Answer : Interfaces, like classes, define a set of properties, methods, and events. But unlike classes, interfaces do not provide implementation. They are implemented by classes, and defined as separate entities from classes. 

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Description : In terms of constructors, what is the difference between: public MyDerived() : base() an public MyDerived() in a child class?

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Last Answer : using System; using System.Collections; public class Items : IEnumerable { private string[] contents; public Items(string[] contents) { this.contents = contents; } public IEnumerator GetEnumerator() { ... (string item in items) { Console.WriteLine(item); } Console.ReadLine(); } }

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Description : Class methods to should be marked with what keyword?

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What is the role of the DataReader class in ADO.NET connections?

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If a base class has a number of overloaded constructors, and an inheriting class has a number of overloaded constructors; can you enforce a call from an inherited constructor to a specific base constructor?

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Description : What is an interface class? 

Last Answer : Interfaces, like classes, define a set of properties, methods, and events. But unlike classes, interfaces do not provide implementation. They are implemented by classes, and defined as separate entities from classes.