Why delegates are needed in C Sharp (C#) - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a delegate named MyDelegate that takes no parameters and returns void.

C Sharp (C#)

public delegate [1] MyDelegate();

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

Aint

Bbool

Cstring

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Using a return type other than void when the delegate should not return a value.

The delegate must specify the return type. Here, it returns nothing, so void is correct.

2fill in blank

medium

Complete the code to create an instance of the delegate MyDelegate that points to the method ShowMessage.

C Sharp (C#)

MyDelegate del = new MyDelegate([1]);

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AShowMessage()

BShowMessage

CShow_Message

DshowMessage

Attempts:

3 left

💡 Hint

Common Mistakes

Including parentheses when assigning the method to the delegate.

Using incorrect method name or casing.

When assigning a method to a delegate, use the method name without parentheses.

3fill in blank

hard

Fix the error in the delegate invocation by completing the code to call the delegate instance del.

C Sharp (C#)

del[1];

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A[]

B;

C()

D{}

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to use parentheses to invoke the delegate.

To invoke a delegate, use parentheses like calling a method.

4fill in blank

hard

Fill both blanks to declare a delegate that takes an int parameter and returns a string.

C Sharp (C#)

public delegate [1] MyDelegate([2] number);

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

Astring

Bint

Cvoid

Dbool

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up return type and parameter type.

Using void as return type when a string is expected.

The delegate returns a string and takes an int parameter named number.

5fill in blank

hard

Fill all three blanks to create a delegate instance that points to the method GetMessage and invoke it.

C Sharp (C#)

MyDelegate del = new [1]([2]);
string result = del[3];

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

AMyDelegate

BGetMessage

C()

DShowMessage

Attempts:

3 left

💡 Hint

Common Mistakes

Using method name with parentheses when creating the delegate.

Forgetting parentheses when invoking the delegate.

Create the delegate instance with the delegate type and method name, then invoke it with parentheses.