How do I get all the subcomponent form values when I iterate through the form subcomponent

[wanxue0804]

I have a form component that I'm iterating over based on the number of bannerArray, and now how do I get the form input value from the form above all the subcomponents through formRef

this.state.bannerArray.map((item, index) => { return <BannerCard wrappedComponentRef={(form) => this.formRef = form} key={index} zone={index} {...props} /> })