How to Efficiently Determine the Existence of a Local Storage Item?

Determining the Existence of a Local Storage Item

When working with web storage, it's crucial to verify the existence of specific items before accessing or modifying them. In this case, we want to determine whether a particular item is set in localStorage.

Current Approach

The current method for checking the existence of an item appears to be:

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

Improved Approach

However, a simplified and more efficient way to check for the existence of an item is to utilize the null return value of the getItem method. According to the WebStorage specification, if the item doesn't exist in the storage, getItem explicitly returns null.

Therefore, you can use the following code to check for the existence of an item:

<code class="javascript">if (localStorage.getItem("infiniteScrollEnabled") === null) {
  //...
}</code>

Additional Resources

For further information on this topic, you may find the following resource helpful:

• [Storing Objects in HTML5 localStorage](link to relevant resource)

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