Technical Interview Questions

1. Does C# support multiple-inheritance?
   No.
2. Who is a protected class-level variable available to?
   It is available to any sub-class (a class inheriting this class).
3. Are private class-level variables inherited?
   Yes, but they are not accessible.  Although they are not visible or accessible via the class interface, they are inherited.
4. Describe the accessibility modifier “protected internal”.
   It is available to classes that are within the same assembly and derived from the specified base class.
5. What’s the top .NET class that everything is derived from?
   System.Object.

1. What is the syntax to inherit from a class in C#?
   Place a colon and then the name of the base class.
   Example: class MyNewClass : MyBaseClass
2. Can you prevent your class from being inherited by another class?
   Yes.  The keyword “sealed” will prevent the class from being inherited.
3. Can you allow a class to be inherited, but prevent the method from being over-ridden?
   Yes.  Just leave the class public and make the method sealed.
4. What’s an abstract class?
   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.

Method and Property Questions

1. What’s the implicit name of the parameter that gets passed into the set method/property of a class?
   Value.  The data type of the value parameter is defined by whatever data type the property is declared as.
   
2. What does the keyword “virtual” declare for a method or property?
   The method or property can be overridden.
3. How is method overriding different from method overloading?
   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.
   

1. Is XML case-sensitive?
   Yes.
   
2. What’s the difference between // comments, /* */ comments and /// comments?
   Single-line comments, multi-line comments, and XML documentation comments.
3. How do you generate documentation from the C# file commented properly with a command-line compiler?
   Compile it with the /doc switch.

1. What debugging tools come with the .NET SDK?
   1.   CorDBG – command-line debugger.  To use CorDbg, you must compile the original C# file using the /debug switch.
   2.   DbgCLR – graphic debugger.  Visual Studio .NET uses the DbgCLR.
   
2. What does assert() method do?
   In debug compilation, assert takes in a Boolean condition as a parameter, and shows the error dialog if the condition is false.  The program proceeds without any interruption if the condition is true.
   
3. What’s the difference between the Debug class and Trace class?
   Documentation looks the same.  Use Debug class for debug builds, use Trace class for both debug and release builds.