Will changing the state caused by useEffect affect the component's re-rendering?

Yes, a state change triggered inside useEffect can lead to a component re-render. When a state update function (e.g., setState) is called within useEffect, React updates the component's state, which causes a re-render.

It is important to avoid infinite update loops, for example, if useEffect depends on a state that it also modifies, dependencies should be correctly specified or conditional checks should be used.

Example:

useEffect(() => {
  setCount(count + 1); // state change
}, []); // empty dependency array — the effect runs once

In this example, the re-render will occur once after the component mounts.