Microsoft Certified Solutions Developer (MCSD) Certification Practice Test

What is the purpose of the AttributeUsage attribute?

1. To specify the targets for a custom attribute

2. To manage resource disposal

3. To sort elements of a collection

4. To implement iterators

The correct answer is: To specify the targets for a custom attribute

The purpose of the AttributeUsage attribute is to specify the targets for a custom attribute. This attribute allows developers to define where a custom attribute can be applied within their code, such as to classes, methods, properties, or other program elements. By using the AttributeUsage attribute, the developer can enforce the intended usage of the custom attribute, ensuring it is applied in the appropriate contexts as designed. For instance, if a developer creates a custom attribute intended for use on methods only, applying the AttributeUsage attribute with the appropriate parameter will restrict its application to method declarations. This improves code clarity and helps maintain proper usage patterns throughout the codebase. Additionally, the AttributeUsage attribute provides options to define whether an attribute can be applied multiple times to a single element or whether it can be inherited by derived classes, providing further control over how the custom attribute functions within the application. The other options do not relate to the functionality of the AttributeUsage attribute. Managing resource disposal pertains to the IDisposable interface, sorting elements relates to collection sorting mechanisms, and implementing iterators involves the use of the IEnumerable interface and the yield statement. Each of these has distinct purposes and functionalities unrelated to defining custom attribute application targets.