Angular 2 getting only the dirty values in a controlgroup

Question

I have a form in Angular 2 that works with a custom ControlGroup. At the moment, when I submit my form, I pass all the data with the following line to my controller.

Answer 1

With the new changes to the Angular Forms I've slightly modified the accepted answer, so it works. Decided to share if anyone is interested. (using Angular 4+)

getDirtyValues(form: any) {
        let dirtyValues = {};

        Object.keys(form.controls)
            .forEach(key => {
                const currentControl = form.controls[key];

                if (currentControl.dirty) {
                    if (currentControl.controls)
                        dirtyValues[key] = this.getDirtyValues(currentControl);
                    else
                        dirtyValues[key] = currentControl.value;
                }
            });

        return dirtyValues;
}