Foreach loop over collections in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to loop through each number in the array and print it.

C Sharp (C#)

int[] numbers = {1, 2, 3, 4, 5};
foreach ([1] number in numbers)
{
    Console.WriteLine(number);
}

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

Adouble

Bstring

Cvar

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Using string or double instead of int causes errors.

Leaving out the type before the variable name.

The foreach loop requires the type of the elements in the collection. Since numbers is an array of int, we use int before the variable name.

2fill in blank

medium

Complete the code to loop through each character in the string and print it.

C Sharp (C#)

string word = "hello";
foreach ([1] ch in word)
{
    Console.WriteLine(ch);
}

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

Achar

Bstring

Cint

Dvar

Attempts:

3 left

💡 Hint

Common Mistakes

Using string instead of char causes errors.

Using int which is not the correct type for characters.

A string is a collection of characters. The foreach loop variable should be of type char to represent each character.

3fill in blank

hard

Fix the error in the foreach loop to correctly iterate over the list of strings.

C Sharp (C#)

List<string> fruits = new List<string> {"apple", "banana", "cherry"};
foreach (string [1] in fruits)
{
    Console.WriteLine([1]);
}

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

Afruits

Bfruit

Citem

Df

Attempts:

3 left

💡 Hint

Common Mistakes

Using the collection name fruits as the loop variable.

Using a variable name that is not descriptive.

The loop variable should be a single element from the collection. Using fruit is correct. Using fruits (the collection name) causes confusion and errors.

4fill in blank

hard

Fill both blanks to create a foreach loop that prints each key and value from the dictionary.

C Sharp (C#)

Dictionary<string, int> ages = new Dictionary<string, int> { {"Alice", 30}, {"Bob", 25} };
foreach (KeyValuePair<[1], [2]> entry in ages)
{
    Console.WriteLine($"{entry.Key} is {entry.Value} years old.");
}

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

Astring

Bint

Cdouble

Dchar

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the key and value types.

Using types not matching the dictionary declaration.

The dictionary has keys of type string and values of type int. The KeyValuePair generic requires these types in order.

5fill in blank

hard

Fill all three blanks to create a foreach loop that prints each character and its index from the string.

C Sharp (C#)

string text = "code";
int index = 0;
foreach ([1] ch in text)
{
    Console.WriteLine($"Character {index}: {ch}");
    index [2] [3];
}

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

Achar

B+=

C1

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Using int as the loop variable type instead of char.

Using ++ instead of += (both work but only one is in options).

Forgetting to increment the index.

The loop variable is a char because we iterate over characters. To increase the index by one each time, use index += 1;.