Read-only and write-only properties in C Sharp (C#) - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of a read-only property

What is the output of this C# code snippet?

C Sharp (C#)

class Person {
    private string name = "Alice";
    public string Name {
        get { return name; }
    }
}

var p = new Person();
Console.WriteLine(p.Name);

A Alice

B null

C Compilation error

D Empty string

💡 Hint

Look at the get accessor and the initial value of the private field.

The property 'Name' has only a get accessor returning the private field 'name' which is initialized to "Alice". So printing p.Name outputs "Alice".

❓ Predict Output

intermediate

Effect of write-only property

What happens when you try to read a write-only property in this code?

C Sharp (C#)

class Secret {
    private string code;
    public string Code {
        set { code = value; }
    }
}

var s = new Secret();
s.Code = "1234";
Console.WriteLine(s.Code);

A Compilation error

B null

C Runtime exception

D 1234

💡 Hint

Check if the property has a get accessor.

The property 'Code' has only a set accessor and no get accessor. Trying to read s.Code causes a compilation error.

🧠 Conceptual

advanced

Understanding read-only auto-properties

Which statement about this code is true?

C Sharp (C#)

class Data {
    public int Value { get; } = 10;
}

var d = new Data();
d.Value = 20;

A Runtime exception when assigning 20

B Value is updated to 20 successfully

C Compilation error because Value has no set accessor

D Value remains 10 but no error

💡 Hint

Check if the property allows assignment outside the constructor.

The property 'Value' has only a get accessor and is initialized inline. Assigning to it outside the constructor causes a compilation error.

❓ Predict Output

advanced

Behavior of write-only property with backing field

What is the output of this code?

C Sharp (C#)

class Box {
    private int size = 5;
    public int Size {
        set { size = value; }
    }
    public int GetSize() => size;
}

var b = new Box();
b.Size = 10;
Console.WriteLine(b.GetSize());

A 5

B 10

C Compilation error

D 0

💡 Hint

The property sets the private field, and GetSize returns it.

The write-only property 'Size' sets the private field 'size'. After setting b.Size = 10, calling GetSize returns 10.

🔧 Debug

expert

Why does this read-only property cause a compilation error?

Identify the cause of the compilation error in this code snippet.

C Sharp (C#)

class Counter {
    private int count;
    public int Count {
        get { return count; }
    }

    public void Increment() {
        Count++;
    }
}

A The Count property causes a stack overflow due to recursive get/set

B The Count property cannot be incremented because the set accessor is private

C The Increment method syntax is invalid

D The Count property is missing a set accessor

💡 Hint

Consider what happens when Count++ is executed with this property implementation.

The property 'Count' has only a get accessor (read-only). Count++ requires both get and set accessors: it reads the value then assigns the incremented value back. Without a set accessor, it causes a compilation error.