如何在页面刷新时保留状态值

时间:2018-09-03 10:13:47

标签: reactjs redux

我正在使用localstorage.setItem()存储状态,该状态将在页面刷新时起作用,但在我的情况下localstorage无法正常工作。页面刷新时我的状态不是持久的。
 我需要全局保存用户ID,这也需要在整个项目的页面刷新中保留。请帮助我解决此问题。         任何帮助,将不胜感激。

        function setUserId(user_id = '', action) {
          switch (action.type) {
            case 'ADD_ID':
            return user_id = action.id;
            default:
            return user_id = action.id;
          }
        }
        const loadState = () => {
          try {
            const serializedState = localStorage.getItem("state");

            if (serializedState === null) {
              return undefined;
            }

            return JSON.parse(serializedState);

          } catch (err) {
            return undefined;
          }
        };

        const store = createStore(setUserId,loadState());

        function saveState(state) {
                try {
                    let serializedState = JSON.stringify(state);
                    localStorage.setItem("state",serializedState);
                }
                catch (err) {
                }
            }

        handleClick(event) {
      let that = this;
      axios.post(apiBaseUrl, payload)
      .then(function (response) {
        console.log(response);
        if(response.status == 200){
          console.log("Login successfull");
          store.dispatch({
            type: 'ADD_ID',
            id: response.data.id
          })
          store.subscribe(() => {
            //this is just a function that saves state to localStorage
            saveState(store.getState());
          });

          that.setState({
            isLoggedIn: true,
            access_token: response.data.access_token,
            user_id: response.data.id
          })

        }

        else if(response.status == 204){
          console.log("Username password do not match");
          alert("username password do not match")
        }
        else{
          console.log("Username does not exists");
          alert("Username does not exist");
        }
      })
      .catch(function (error) {
        console.log(error);
      });
    }

1 个答案:

答案 0 :(得分:0)

从您的try/catch中删除saveState()。如果要在子组件树的任何位置捕获JavaScript错误。并尝试在state的{​​{1}}中进行控制台。