Cannot getItem from sessionStorage in ComponentWillMount?

Question

Just looking to pull in some data sitting in sessionStorage inside of componentWillMount but I continue running into: cannot getItem of undefined . Here is what this looks like:

  componentWillMount() {
    console.log(window.sessionStorage); // logs sessionStorage
    console.log(window.sessionStorage.getItem('some-key')); // errors out here
  }

EDIT: Here is a screenshot. The key is different because I was just using something else for the example, but the error is the same.

Here is the error: TypeError: Cannot read property "getItem" from undefined . Odd enough, it works in componentDidMount .

For clarification: I'm using window.sessionStorage instead of sessionStorage because for some reason it can't recognize it without appending it to the window object.

Found one or two other questions on similar topics but nothing to help explain why getItem is not available on sessionStorage .

Answer 1

您可以在ComponentDidMount使用sessionStorage 。

Answer 2

Add this method to your component class(.ts file).

get sessionStorage() {
    return sessionStorage;
}