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DIFFERENT parameter DATA types, different NUMBER of PARAMETERS, different order of parameters.

Different parameter data types, different number of parameters, different order of parameters.

No. The signature of the virtual METHOD MUST remain the same. (NOTE: Only the KEYWORD virtual is changed to keyword override)

No. The signature of the virtual method must remain the same. (Note: Only the keyword virtual is changed to keyword override)

When overriding a method, you CHANGE the behavior of the method for the derived class. OVERLOADING a method simply involves having another method with the same NAME WITHIN the class.

When overriding a method, you change the behavior of the method for the derived class. Overloading a method simply involves having another method with the same name within the class.

The METHOD or PROPERTY can be OVERRIDDEN.

The method or property can be overridden.

VALUE. The DATA type of the value PARAMETER is DEFINED by whatever data type the property is declared as.

Value. The data type of the value parameter is defined by whatever data type the property is declared as.

Structs are value-type variables and are THUS saved on the STACK, additional overhead but FASTER retrieval. Another DIFFERENCE is that structs cannot inherit.

Structs are value-type variables and are thus saved on the stack, additional overhead but faster retrieval. Another difference is that structs cannot inherit.

In an interface class, all METHODS are abstract - there is no IMPLEMENTATION. In an abstract class some methods can be concrete. In an interface class, no ACCESSIBILITY modifiers are ALLOWED. An abstract class may have accessibility modifiers.

In an interface class, all methods are abstract - there is no implementation. In an abstract class some methods can be concrete. In an interface class, no accessibility modifiers are allowed. An abstract class may have accessibility modifiers.

It’s up to you to implement the method inside your own CLASS, so IMPLEMENTATION is left entirely up to you. This might cause a problem on a higher-level scale if SIMILARLY named methods from different interfaces EXPECT different data, but as far as compiler cares you’re okay.
To Do: Investigate.

It’s up to you to implement the method inside your own class, so implementation is left entirely up to you. This might cause a problem on a higher-level scale if similarly named methods from different interfaces expect different data, but as far as compiler cares you’re okay.
To Do: Investigate.

YES. .NET does SUPPORT MULTIPLE INTERFACES.

Yes. .NET does support multiple interfaces.

They all MUST be PUBLIC, and are THEREFORE public by DEFAULT.

They all must be public, and are therefore public by default.

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.

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.

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.

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.

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.

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.

Yes. Just leave the class public and MAKE the METHOD SEALED.

Yes. Just leave the class public and make the method sealed.

YES. The KEYWORD “SEALED” will prevent the class from being INHERITED.

Yes. The keyword “sealed” will prevent the class from being inherited.

PLACE a COLON and then the NAME of the BASE class.
Example: class MyNewClass : MyBaseClass.

Place a colon and then the name of the base class.
Example: class MyNewClass : MyBaseClass.

The answer is False because it is given that A.equals(B) RETURNS true i.e. objects are equal and now its hash Code is asked which is ALWAYS independent of the fact that whether objects are equal or not. So, GET HashCode for both of the objects returns different value.

The answer is False because it is given that A.equals(B) returns true i.e. objects are equal and now its hash Code is asked which is always independent of the fact that whether objects are equal or not. So, Get HashCode for both of the objects returns different value.

Presentation (UI), Business (logic and underlying CODE) and DATA (from STORAGE or other SOURCES).

Presentation (UI), Business (logic and underlying code) and Data (from storage or other sources).

No. Once the PROPER CATCH block PROCESSED, control is transferred to the FINALLY block (if there are any).

No. Once the proper catch block processed, control is transferred to the finally block (if there are any).

A catch BLOCK that catches the exception of type System.Exception. You can ALSO OMIT the PARAMETER data type in this case and just write catch {}.

A catch block that catches the exception of type System.Exception. You can also omit the parameter data type in this case and just write catch {}.

YES. FINALLY block always GET EXECUTED.

Yes. Finally block always get executed.

A SORTED HASHTABLE.

A sorted HashTable.

HASHTABLE, DICTIONARY, NameValueCollection.

HashTable, Dictionary, NameValueCollection.

System.String is IMMUTABLE. System.StringBuilder was DESIGNED with the PURPOSE of having a MUTABLE string where a variety of operations can be PERFORMED.

System.String is immutable. System.StringBuilder was designed with the purpose of having a mutable string where a variety of operations can be performed.

The data value may not be CHANGED. NOTE: The variable value may be changed, but the ORIGINAL immutable data value was DISCARDED and a new data value was CREATED in memory.

The data value may not be changed. Note: The variable value may be changed, but the original immutable data value was discarded and a new data value was created in memory.

System.Object.

System.Object.

It is AVAILABLE to classes that are within the same ASSEMBLY and DERIVED from the SPECIFIED base class.

It is available to classes that are within the same assembly and derived from the specified base class.

YES, but they are not ACCESSIBLE. Although they are not visible or accessible VIA the class interface, they are inherited.

Yes, but they are not accessible. Although they are not visible or accessible via the class interface, they are inherited.

It is AVAILABLE to any sub-CLASS (a class INHERITING this class).

It is available to any sub-class (a class inheriting this class).

No, but you can IMPLEMENT more than ONE INTERFACES.

No, but you can implement more than one interfaces.

No, a STATIC CLASS can CONTAIN only static MEMBERS.

No, a static class can contain only static members.

No, you cannot CREATE an INSTANCE of a STATIC CLASS.

No, you cannot create an instance of a static class.

FALSE, only CLASSES can be DECLARED as STATIC and not STRUCTS.

False, only classes can be declared as static and not structs.

USE the sealed KEYWORD to prevent a class from being INHERITED by ANOTHER class.

Use the sealed keyword to prevent a class from being inherited by another class.

No, you cannot CREATE an INSTANCE for an ABSTRACT CLASS.

No, you cannot create an instance for an abstract class.

YES, the derived class will AUTOMATICALLY contain all the PUBLIC, protected, and internal members of the BASE class except its constructors and destructors.

Yes, the derived class will automatically contain all the public, protected, and internal members of the base class except its constructors and destructors.

False, Only classes SUPPORT INHERITANCE. STRUCTS DONOT support inheritance.

False, Only classes support inheritance. structs donot support inheritance.

private.

private.

1. public
2. protected
3. internal
4. protected internal
5. PRIVATE

1. public
2. protected
3. internal
4. protected internal
5. private

A class is used to model more complex BEHAVIOR, or DATA that is INTENDED to be modified after a class object is CREATED. A struct is best suited for SMALL data structures that contain primarily data that is not intended to be modified after the struct is created.

A class is used to model more complex behavior, or data that is intended to be modified after a class object is created. A struct is best suited for small data structures that contain primarily data that is not intended to be modified after the struct is created.

A STRUCT is a value TYPE mean when a struct is created, the variable to which the struct is assigned holds the struct's actual data. When the struct is assigned to a NEW variable, it is copied. The new variable and the original variable therefore contain TWO separate copies of the same data. CHANGES made to one copy do not affect the other copy.

A struct is a value type mean when a struct is created, the variable to which the struct is assigned holds the struct's actual data. When the struct is assigned to a new variable, it is copied. The new variable and the original variable therefore contain two separate copies of the same data. Changes made to one copy do not affect the other copy.

A class is a REFERENCE type means when an object of the class is created, the VARIABLE to which the object is assigned holds only a reference to that MEMORY. When the object reference is assigned to a NEW variable, the new variable refers to the original object. Changes made through one variable are reflected in the other variable because they both REFER to the same data.

A class is a reference type means when an object of the class is created, the variable to which the object is assigned holds only a reference to that memory. When the object reference is assigned to a new variable, the new variable refers to the original object. Changes made through one variable are reflected in the other variable because they both refer to the same data.

All STRUCTS INHERIT DIRECTLY from System.ValueType, which INHERITS from System.Object.

All structs inherit directly from System.ValueType, which inherits from System.Object.

STRUCTS are VALUE TYPES.

Structs are value types.

Yes.

Yes.

No, a STRUCT cannot INHERIT from ANOTHER struct or CLASS, and it cannot be the BASE of a class.

No, a struct cannot inherit from another struct or class, and it cannot be the base of a class.

YES, you can INSTANTIATE a struct without using a NEW operator.

Yes, you can instantiate a struct without using a new operator.

No.

No.

No, C# supports single class INHERITANCE only. HOWEVER CLASSES can implement MULTIPLE interfaces at the same time.

No, C# supports single class inheritance only. However classes can implement multiple interfaces at the same time.

CODE REUSE.

Code reuse.