Passing reference types to methods in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to pass the object to the method.

C Sharp (C#)

class Program {
    static void Main() {
        Person p = new Person();
        UpdateName([1]);
    }

    static void UpdateName(Person person) {
        person.Name = "Alice";
    }
}

class Person {
    public string Name { get; set; }
}

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Anew Person()

BPerson

Cp

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the class name instead of the object variable.

Passing null instead of the object.

You need to pass the existing object p to the method to update its name.

2fill in blank

medium

Complete the method call to change the age of the person.

C Sharp (C#)

class Program {
    static void Main() {
        Person p = new Person();
        SetAge([1], 30);
    }

    static void SetAge(Person person, int age) {
        person.Age = age;
    }
}

class Person {
    public int Age { get; set; }
}

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Anew Person()

Bp

CPerson

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a new object instead of the existing one.

Passing the class name instead of an object.

You must pass the existing object p to update its age.

3fill in blank

hard

Fix the error in the method to correctly update the person's city.

C Sharp (C#)

class Program {
    static void Main() {
        Person p = new Person();
        ChangeCity(p);
        System.Console.WriteLine(p.City);
    }

    static void ChangeCity(Person person) {
        person.City = [1];
    }
}

class Person {
    public string City { get; set; }
}

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Anull

BNew York

Cperson.City

D"New York"

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the string.

Using an undefined variable.

The city name must be a string literal with quotes.

4fill in blank

hard

Fill both blanks to create a method that updates the person's name and age.

C Sharp (C#)

class Program {
    static void Main() {
        Person p = new Person();
        UpdatePerson(p, [1]);
        System.Console.WriteLine($"Name: {p.Name}, Age: {p.Age}");
    }

    static void UpdatePerson(Person person, int newAge) {
        person.Name = [2];
        person.Age = newAge;
    }
}

class Person {
    public string Name { get; set; }
    public int Age { get; set; }
}

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A"Bob"

B25

C"Alice"

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the wrong type for age.

Not using quotes for the name string.

The method call passes the new age 25 and sets the name to "Bob".

5fill in blank

hard

Fill all three blanks to create a method that updates name, age, and city of a person.

C Sharp (C#)

class Program {
    static void Main() {
        Person p = new Person();
        UpdateDetails(p, [1], [2], [3]);
        System.Console.WriteLine($"Name: {p.Name}, Age: {p.Age}, City: {p.City}");
    }

    static void UpdateDetails(Person person, string newName, int newAge, string newCity) {
        person.Name = newName;
        person.Age = newAge;
        person.City = newCity;
    }
}

class Person {
    public string Name { get; set; }
    public int Age { get; set; }
    public string City { get; set; }
}

Drag options to blanks, or click blank then click option'

A"Charlie"

B40

C"Seattle"

D"Denver"

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the order of arguments.

Forgetting quotes around string arguments.

The method call passes name "Denver", age 40, and city "Seattle".