ASP.NET学习社区

C#面试题目1.Does C# support multiple-inheritance?
no.
2.Who is a protected class-level  variable avaiable to?
It is available to any sub-class(a class inherting this class)
3.Are private class-level variables inherited?
Yes,but they are not accessible. Although they are not visible or accessible via class
interface ,they are inherited.
4.Descible the accessibility modifier "protected intenal".
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 is the top .NET class that everything is derived from?
System.Object.
6.What does the term immutable mean?
Immutable means that the date value may not be changed.
Note: The variable value may be changed,but the variable value may be
changed ,the orignal immutable value was discarded and a new data was created
in the memory.
7.  What’s the difference between System.String and System.Text.StringBuilder classes?
System.String is immutable.  System.StringBuilder was designed with the purpose of having a mutable string where a variety of operations can be performed.

8.What’s the advantage of using System.Text.StringBuilder over System.String?
StringBuilder is more efficient in cases where there is a large amount of string manipulation.  Strings are immutable, so each time a string is changed, a new instance in memory is created.
9.Can you store multiple data types in System.Array?
No.