Attribute targets and usage in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify that the attribute can only be applied to classes.

C Sharp (C#)

[AttributeUsage([1])]
public class MyCustomAttribute : Attribute
{
}

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AAttributeTargets.Class

BAttributeTargets.Method

CAttributeTargets.Property

DAttributeTargets.Field

Attempts:

3 left

💡 Hint

Common Mistakes

Using AttributeTargets.Method or other targets instead of AttributeTargets.Class.

The AttributeUsage attribute specifies that MyCustomAttribute can only be applied to classes by using AttributeTargets.Class.

2fill in blank

medium

Complete the code to allow the attribute to be applied multiple times on the same element.

C Sharp (C#)

[AttributeUsage(AttributeTargets.Method, [1] = true)]
public class RepeatableAttribute : Attribute
{
}

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AInherited

BAllowMultiple

CValidOn

DMultipleAllowed

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Inherited' or incorrect property names like 'ValidOn' or 'MultipleAllowed'.

The AllowMultiple property set to true allows the attribute to be applied multiple times on the same method.

3fill in blank

hard

Fix the error in the attribute usage by completing the code with the correct target.

C Sharp (C#)

[AttributeUsage([1])]
public class SampleAttribute : Attribute
{
}

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AAttributeTargets.Namespace

BAttributeTargets.ReturnValue

CAttributeTargets.Parameter

DAttributeTargets.Class | AttributeTargets.Method

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid targets like Namespace or only one target when multiple are needed.

The attribute is intended to be used on classes and methods, so the correct target is a combination of AttributeTargets.Class and AttributeTargets.Method using the bitwise OR operator.

4fill in blank

hard

Fill both blanks to create an attribute that can be inherited and applied to properties.

C Sharp (C#)

[AttributeUsage([1], [2] = true)]
public class InheritablePropertyAttribute : Attribute
{
}

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AAttributeTargets.Property

BAllowMultiple

CInherited

DAttributeTargets.Field

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing AllowMultiple with Inherited or using wrong targets like Field.

The attribute targets properties using AttributeTargets.Property and is set to be inherited by derived classes with Inherited = true.

5fill in blank

hard

Fill all three blanks to define an attribute that targets methods, allows multiple usage, and is not inherited.

C Sharp (C#)

[AttributeUsage([1], [2] = true, [3] = false)]
public class CustomMethodAttribute : Attribute
{
}

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

AAttributeTargets.Method

BAllowMultiple

CInherited

DAttributeTargets.Class

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up AllowMultiple and Inherited or using wrong targets.

The attribute targets methods (AttributeTargets.Method), allows multiple usage (AllowMultiple = true), and is not inherited (Inherited = false).