javascript - Next Js Router beforePopState ，在 handler 中访问组件的状态

Question

我正在使用 Next js Router.beforePopState 事件，我想访问我在定义此处理程序的 react 组件中创建的 useState 变量的值，示例代码如下，但每当我访问状态时，它为空或设置为默认值下面代码中的示例 离开即使我在代码中设置了不同的值，我总是在处理程序中以空字符串“”的形式获取状态值，有没有办法可以在处理程序中获取状态值？

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;
     });
   };
 }, []);

Answer 1

我能够找到相同的解决方案，我缺少的是在 useEffect 中添加属性，下面的代码修复了问题-

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