useSubmitThe imperative version of <Form> that lets you, the programmer, submit a form instead of the user.
For example, submitting the form every time a value changes inside the form:
import { useSubmit, Form } from "react-router-dom";
function SearchField() {
  let submit = useSubmit();
  return (
    <Form
      onChange={(event) => {
        submit(event.currentTarget);
      }}
    >
      <input type="text" name="search" />
      <button type="submit">Search</button>
    </Form>
  );
}
This can also be useful if you'd like to automatically sign someone out of your website after a period of inactivity. In this case, we've defined inactivity as the user hasn't navigated to any other pages after 5 minutes.
import { useSubmit, useLocation } from "react-router-dom";
import { useEffect } from "react";
function AdminPage() {
  useSessionTimeout();
  return <div>{/* ... */}</div>;
}
function useSessionTimeout() {
  const submit = useSubmit();
  const location = useLocation();
  useEffect(() => {
    const timer = setTimeout(() => {
      submit(null, { method: "post", action: "/logout" });
    }, 5 * 60_000);
    return () => clearTimeout(timer);
  }, [submit, location]);
}
The first argument to submit accepts many different values.
You can submit any form or form input element:
// input element events
<input onChange={(event) => submit(event.currentTarget)} />;
// React refs
let ref = useRef();
<button ref={ref} />;
submit(ref.current);
You can submit FormData:
let formData = new FormData();
formData.append("cheese", "gouda");
submit(formData);
The second argument is a set of options that map directly to form submission attributes:
submit(null, {
  action: "/logout",
  method: "post",
});
// same as
<Form action="/logout" method="post" />;