C# 笔试题，看你会几道题

1. Which interface you need to implement to support for each?

IEnumerator

IEnumerable

IComparer

IComparable

All of the above

None of the above

2. What is the “internal” keyword used for?

To make a method to be used internally by the declaring class only.

To make a field that is accessed by multiple threads.

To use with the DllImport attribute when using Interop services to call into unmanaged code.

None of the above

3. Read the following 2 statements about const and read-only field

A const field can only be initialised where it’s declared. A read-only field can be initialised where it’s declared or in a constructor.

A const field is set at compile time, but a read-only field is set at run time.

4. Read the following statements about structs.

Structs are value types.

Structs are reference types.

Structs can be directly derived from System.Object.

Structs can be directly derived from System.ValueType.

Structs only allocate memory from stack.

5. What is the keyword “delegate” used for?

Another visibility modifier like public, private, protected

Used in multi threaded programs to protect a variable

Used to define a method signature type that can be used as a typed variable

None of the above

6. What is “boxing”?

Wrapping an object into a value type

Wrapping a value type into an object

Wrapping a collection into a byte array

None of the above

7. Can I use “return” statement inside a “final” block?

Yes

No

8. Is Delegate a type of Event?

Yes

No

9. If x.Equals(y) is true. Is it correct that x.GetHashcode() != y.GetHashcode()?

Yes

No

10. int keyword targets to which .Net type?
System.Int8

System.Int16

System.Int32

System.Int64