如何在javascript中获取以前的网址？

Question

I need to get the previous url in a nextjs project. I found this but it doesn't help because it always prints me the base url ( http://localhost:3000/ ) with this method ( document.referrer ). I also tried to push a state into window.history based on official developer mozilla doc.

In the last case I click on a link and it redirects me to another page. On this page I need to know where I come from. I tried:

//pathname is a string containing the actual pathname
history.pushState({prevPath: pathname},pathname)

If I print history in the new page then I don't see any prevState in the state field.

Answer 1

You can simply create a state which is an object that has two properties: previousUrl and currentUrl like this:

const urlReducer = (state={previousUrl: null, currentURL: null},action) => {
    switch(action.type){
        case "SET_URLS":
            return {previousUrl: state.currentUrl, currentUrl: window.location.href}
        default:
            return state;
    }
}

Then all you need to do is dispatch an action in every page you visit like this:

const dispatch = useDispatch();

useEffect(()=>{
    dispatch({type: "SET_URLS"});
},[]);