Question

我正在使用Next js Router.beforePopState事件，我想访问在其中定义了该处理程序的react组件中创建的useState变量的值，下面是示例代码，但是每当我访问该状态时，它为空或设置为默认值，例如下面的代码 goaway 状态值，即使我在代码中设置了其他值，我也总是以空字符串“”的形式进入处理程序，有没有办法在处理程序中获取状态值？

hasOwnProperty

Answer 1

我能够找到与我所缺少的解决方案相同的解决方案，即在useEffect中添加属性，以下代码修复了该问题-

const [goAway, setGoAway] = useState("");


 const browserTabcloseHandler = e => {
   e.preventDefault(); // If you prevent default behavior in Mozilla Firefox prompt will always be shown
   // Chrome requires returnValue to be set
   e.returnValue = "";
 };

 useEffect(() => {
   if (window) {
     Router.beforePopState(() => {
       //if (componentShouldBeSavedAsDraft(componentData)) {
       const result = window.confirm("are you sure you want to leave?");
       if (!result) {
         window.history.pushState("/", "");
         Router.push("/marketplace/upload-component");
       }
       console.log(goAway); // this value is always "" even though set differently in code. 
       return result;
     });
     window.onbeforeunload = browserTabcloseHandler;
   }
   //Router.events.on("routeChangeStart", handleRouteChange);

   return () => {
     if (window) {
       window.onbeforeunload = null;
     }
     Router.beforePopState(() => {
       return true;
     });
   };
 }, [goAway]); // this fixed the issue

下一个Js Router beforePopState，处理程序中组件的访问状态

1 个答案: