How do I use property decorators in TypeScript?

How do I use property decorators in TypeScript?

Property decorators in TypeScript are special functions that can be applied to class properties. They allow you to modify the behavior of the property, such as adding validation or logging.

Can you give me an example of a property decorator?

Sure! Here's a simple example:

function Log(target: any, propertyKey: string) {
    let value = target[propertyKey];
    const getter = () => value;
    const setter = (newValue) => {
        console.log(`Setting value '${newValue}' to '${propertyKey}'`);
        value = newValue;
    };
    Object.defineProperty(target, propertyKey, { get: getter, set: setter });
}

class Person {
    @Log
    name: string;
}

In this example, whenever you set the name property, it will log the new value.

What are some common use cases for property decorators?

Common use cases include validation, logging, and automatic property binding in frameworks like Angular. They help in managing property behavior more effectively.

Are there any limitations to using property decorators?

Yes, property decorators can only be used on class properties, and they cannot be used on methods or parameters. Additionally, they may introduce complexity if overused.