Get and set accessors in C Sharp (C#) - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this C# code using get and set accessors?

Consider the following C# class with a property using get and set accessors. What will be printed when the program runs?

C Sharp (C#)

class Person {
    private string name;
    public string Name {
        get { return name; }
        set { name = value.ToUpper(); }
    }
}

class Program {
    static void Main() {
        Person p = new Person();
        p.Name = "alice";
        System.Console.WriteLine(p.Name);
    }
}

A null

B alice

C Alice

D ALICE

💡 Hint

Look at how the set accessor modifies the value before storing it.

The set accessor converts the input string to uppercase before storing it in the private field. So when we get the Name property, it returns the uppercase version.

❓ Predict Output

intermediate

What value does the property return after setting it?

Given this C# code, what will be the output?

C Sharp (C#)

class Counter {
    private int count;
    public int Count {
        get { return count; }
        set {
            if (value >= 0) count = value;
        }
    }
}

class Program {
    static void Main() {
        Counter c = new Counter();
        c.Count = -5;
        System.Console.WriteLine(c.Count);
    }
}

A -5

B 0

C Throws an exception

D Uninitialized value

💡 Hint

Check what happens when the set accessor receives a negative value.

The set accessor only assigns the value if it is zero or positive. Since -5 is negative, the private field remains at its default value 0.

🔧 Debug

advanced

Why does this property cause a stack overflow error?

Examine the following C# property. Why does it cause a runtime error?

C Sharp (C#)

class Sample {
    private int number;
    public int Number {
        get { return Number; }
        set { Number = value; }
    }
}

A The get and set accessors recursively call themselves causing a stack overflow.

B The private field 'number' is not initialized causing a null reference exception.

C The property is missing a semicolon causing a syntax error.

D The property uses an invalid data type causing a compile error.

💡 Hint

Look at what the get and set accessors are returning and assigning.

The get accessor returns the property itself, not the private field, so it calls itself infinitely. The set accessor also assigns to the property, causing infinite recursion. This leads to a stack overflow error.

📝 Syntax

advanced

Which option correctly defines a read-only property with a private set accessor?

Choose the correct C# property syntax that allows reading the value publicly but only setting it privately within the class.

A public int Age { get private; set; }

B public int Age { private get; set; }

C public int Age { get; private set; }

D public int Age { get; set; private }

💡 Hint

Remember the correct order and syntax for access modifiers on accessors.

Option C correctly places 'private' before 'set;' to restrict setting access. Other options have invalid syntax or misplaced modifiers.

🚀 Application

expert

How many items are in the dictionary after this code runs?

Analyze this C# code using a property with get and set accessors that modify a dictionary. How many key-value pairs does the dictionary contain after execution?

C Sharp (C#)

class DataStore {
    public Dictionary<string, int> data = new();
    public int this[string key] {
        get => data.ContainsKey(key) ? data[key] : -1;
        set {
            if (value >= 0) data[key] = value;
            else if (data.ContainsKey(key)) data.Remove(key);
        }
    }
}

class Program {
    static void Main() {
        DataStore store = new DataStore();
        store["a"] = 10;
        store["b"] = 20;
        store["a"] = -5;
        store["c"] = 0;
        store["b"] = -1;
        System.Console.WriteLine(store.data.Count);
    }
}

A 1

B 2

C 3

D 0

💡 Hint

Track how the set accessor adds, updates, or removes keys based on the value.

Initially, keys 'a' and 'b' are added. Setting 'a' to -5 removes it. 'c' is added with 0. Setting 'b' to -1 removes it. Only 'c' remains, so count is 1.