c # Question and Answers

1) Explain about C#?
C # is also known as c sharp. It is a programming language introduced by Microsoft.
C# contains features similar to Java and C++. It is specially designed to work with Microsoft .NET platform.

2) Explain about the rules for naming classes in C#?
These are the rules for naming classes in c sharp.
• Must begin with a letter. This letter may be followed by a sequence of letters, digits (0-9), or ‘_’. The first character in a class name cannot be a digit.
• Must not contain any embedded space or symbol like ? - + ! @ # % & * ( ) { } [ ] , : ; ‘ “ \ and/. However an underscore _ can be used wherever a space is required.
• Must not use a keyword for a class name.

3) What are the rules to be followed while naming variables in C#.
The following rules are used for naming variables in C#.
* Must begin with a letter or an underscore _ which may be followed by a sequence of letters, digits (0-9), or ‘_’. The first character in a variable name cannot be a digit.
* Must not contain any embedded space or symbol like ? - + ! @ # % & * ( ) { } [ ] , : ; ‘ “ \ and/. However an underscore _ can be used wherever a space is required.
• Must be unique
• Can have any number of characters
• Keywords cannot be used as variable names.

4) What are the different types of Data?
There are two different types of data supported by C#. They are
1) Value types: -They directly contain data. When you declare an int variable, the system allocates memory to store the value.
2) Reference type: -The reference types do not maintain data but they contain a reference to the variables, which are stored in memory. This means that if the value in the memory location is modified by one of the variables, the other variables automatically reflect the changes value

5) Explain about member functions?
A function is a set of statements that perform a specific task in response to a message. The functions of a class are called member functions in Csharp. Member functions are declared inside the class. The function declaration introduces the function in the class and the function definition contains the function code.

6) Explain about comment entry?
Comments are a part of the program and are used to explain the code. Compilers ignore comment entries. If a comment entry spans more than one line, it has to be enclosed within ‘/*’ and ‘*/’. The symbol ‘//’ treats the rest of code within the same line as a comment.

7) What are operators?
Applications use operators to process the data entered by a user. Operators like + and – are used to process variables and return a value. An operator is a set of one or more characters that is used for computations or comparisons. Operators can transform one or more data values, called operands into a new data value.

8) Explain about the break statement?
A break statement is used to exit the switch statement. This prevents the execution of the remaining case structures by ending the execution of the switch case construct. Each break statement terminates the enclosing switch statement and the flow of control. If none of the cases match the default case is invoked.

9) Define encapsulation?
Encapsulation literally means to enclose in or as if in a capsule. Encapsulation is defined as the process of enclosing one or more items within a physical or logical package. It involves preventing access to nonessential details.

10) Define access specifier with reference to class?
An access specifier defines the scope of a class member. A class member refers to the variables and functions in a class. A program can have one or more classes. You may want some members of a class to be accessible to other classes. But, you may not want some other members of the class to be accessible outside the class.

11) Describe about private access specifier?

The private access specifier allows a class to hide its member variables and member functions from other class objects and functions. Therefore, the private member of a class is not visible outside a class. If a member is declared private, only the functions of that class can access the member. Even the instance of the class cannot access its members

12) Explain about protected internal access specifier?
This specifier allows a class to hide its member variables and member functions to be accessed from other class objects and functions, except the child class, within the application. The protected internal access specifier becomes important while implementing inheritance.

13) Define parameter by value?
Pass by value is the default mechanism for passing parameters to a method. The simplest definition of a value parameter is a data type name followed by a variable name. When a method is called, a new storage location is created for each value parameter. The values of the corresponding expressions are copied into them. The expression supplied for each value parameter must be similar to the declaration of the value parameter.

14) State the methods through which parameters can be passed?
Parameters can be passed by using any one of the following mechanism.
Value: -They are sometimes called in or out parameters; therefore, the data can be transferred into the method but cannot be transferred out.
Reference: -Are sometimes called in or out parameters, therefore, the data can be transferred into the method and out again.
Output: -Are sometimes called out parameters, data can be transferred out of the method.

15) Explain about reference parameter?
A reference parameter is a reference to a memory location of a data member. Unlike a value parameter, a reference parameter does not create a new storage location. Instead a reference parameter represents the same location in memory as the variable that is supplied in the method call.

16) How do you use a structure?
A structure is a value type data type. When you want a single variable to hold related data of various data types, you can create a structure. To create a structure you use the struct keyword.

17) What is an enumerator?
Enumeration is a value data type, which means that enumeration contains its own values and cannot inherit or pass inheritance. Enumerator allows you to assign symbolic names or integral constants.