react how to get refs from child element and store them in a state code example

Example 1: refs react js

class Lesson9Refs extends Component {

    onAddProduct = () => {
        alert(this.refs.productname.value);
    }
    
    
    return (

            


                

                    

                        

                            Featured
                        
                        

                          
                             Product Name: 
                              

                            
                                Add Product
                            

                        
                    
                    

                        { elements }
                    
                
            
        );

    }
}

export default Lesson9Refs;

Example 2: cre&atRefs react js

const node = this.myRef.current;