When encountering the error “null is not an object (evaluating ‘localStorage.getItem’)”, it means that the code is trying to access the getItem method of the localStorage object, but the localStorage object is null or undefined.
To better understand this error, let’s take a look at an example:
localStorage.setItem("name", "John");
var name = localStorage.getItem("name");
console.log(name);
In the example above, we are attempting to store the value “John” with the key “name” in the localStorage. Then, we try to retrieve the value of the key “name” using the getItem method. Finally, we log the value to the console.
However, if the browser does not support localStorage or if it’s disabled, the localStorage object will be null or undefined. In such cases, when we try to call the getItem method on a null or undefined object, we will encounter the mentioned error.
To fix this error, we need to ensure that localStorage is available and accessible. Here’s an example of how we can do that:
if (typeof Storage !== "undefined") {
localStorage.setItem("name", "John");
var name = localStorage.getItem("name");
console.log(name);
} else {
console.log("LocalStorage not supported");
}
In the updated example, we first check if the browser supports the Storage API by checking the typeof Storage. If it’s supported, we proceed with using the localStorage methods. Otherwise, we log an error message.
By adding this check, we can avoid accessing properties or methods of undefined objects and prevent the “null is not an object” error when working with localStorage.