How to check whether a Storage item is set?

javascript html local-storage
Jiew Meng picture Jiew Meng · Jul 16, 2010 · Viewed 357.8k times · Source

How can I check if an item is set in localStorage? Currently I am using

if (!(localStorage.getItem("infiniteScrollEnabled") == true || localStorage.getItem("infiniteScrollEnabled") == false)) {
    // init variable/set default variable for item
    localStorage.setItem("infiniteScrollEnabled", true);
}

Answer

Christian C. Salvadó picture Christian C. Salvadó · Jul 16, 2010

The getItem method in the WebStorage specification, explicitly returns null if the item does not exist:

... If the given key does not exist in the list associated with the object then this method must return null. ...

So, you can:

if (localStorage.getItem("infiniteScrollEnabled") === null) {
  //...
}

See this related question:

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