In this chapter, you'll learn about property validation in React components. This might seem simple at first glance, but it's an important topic because it leads to bug-free components. I'll start things off with a discussion about predictable outcomes and how this leads to components that are portable throughout the application.

Next, you'll walk through examples of some of the type-checking property validators that come with React. Then, you'll walk through some more complex property-validation scenarios. Finally, I'll wrap this chapter up with an example of how to implement your own custom validators.

The following topics will be covered in this chapter:

• Knowing what to expect
• Promoting portable components
• Simple property validators
• Type and value validators
• Writing custom property validators