introduction-decorators-property-decorator-show-info.ts

function showInfo() {
    return (
        target: any,
        propertyKey: string,
        parameterIndex: number,
    ) => {
        console.log('target', target);
        console.log('property key', propertyKey);
        console.log('parameter index', parameterIndex);
    }
}

class User {
    changeName(
        @showInfo() name: string,
    ) {}
}

// target User { changeName: [Function] }
// property key changeName
// parameter index 0