C# - Datatypes Question and Answer

C# - Datatypes Question and Answer
11. Which of the following statements are correct?
 We can assign values of any type to variables of type object.
    When a variable of a value type is converted to object, it is said to be unboxed.
    When a variable of type object is converted to a value type, it is said to be boxed.
    Boolean variable cannot have a value of null.
    When a value type is boxed, an entirely new object must be allocated and constructed.
  • 2, 5
  • 1, 5
  • 3, 4
  • 2, 3
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12. Which of the following is the correct ways to set a value 3.14 in a variable pi such that it cannot be modified?
  • float pi = 3.14F;
  • #define pi 3.14F;
  • const float pi = 3.14F;
  • const float pi; pi = 3.14F;
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13. Which of the following statements are correct about data types?

    Each value type has an implicit default constructor that initializes the default value of that type.
    It is possible for a value type to contain the null value.
    All value types are derived implicitly from System.ValueType class.
    It is not essential that local variables in C# must be initialized before being used.
    Variables of reference types referred to as objects and store references to the actual data.
  • 1, 3, 5
  • 2, 4
  • 3, 5
  • 2, 3, 4
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14. Which of the following are the correct way to initialise the variables i and j to a value 10 each?

    int i = 10; int j = 10;

    int i, j;
    i = 10 : j = 10;

    int i = 10, j = 10;

    int i, j = 10;

    int i = j = 10;
  • 2, 4
  • 1, 3
  • 3, 5
  • 4, 5
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15. Which of the following statement correctly assigns a value 33 to a variable c?

byte a = 11, b = 22, c;
  • c = (byte) (a + b);
  • c = (byte) a + (byte) b;
  • c = (int) a + (int) b;
  • c = (int)(a + b);
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16. Which of the following statements are correct about datatypes in C#.NET?

    Every datatype is either a value type or a reference type.
    Value types are always created on the heap.
    Reference types are always created on the stack.
    Mapping of every value type to a type in Common Type System facilitates Interoperability in C#.NET.
    Every reference type gets mapped to a type in Common Type System.
  • 1, 3
  • 2, 5
  • 1, 4
  • 3, 4
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17. Which of the following is the correct default value of a Boolean type?
  • 0
  • 1
  • True
  • False
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