title: Why we need to use onChange event in react js for the input fields
body: <p>I have a question that why we need to use onchange event in react and set the state on every change event and why we cannot change the state of all the input fields of the form on submit button?
  When we use onChange in an input field, it performs all the inbetween steps to set the state on every change event, so why don't we use event.target to store all the states on submit or it is not possible?</p>