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JavaScript JavaScript and the DOM Making Changes to the DOM Remove Nodes

Display an error message when there are no more list elements to remove?

I was wondering a basic way to display an error message once all task items are removed from the list? I see the console throws an error once all items are removed, so how could display an alert for example? Thanks :)

1 Answer

Steven Parker
Steven Parker
229,004 Points

When there are no more items, the querySelector returns null, and attempting to perform the remove on that causes the error. You can easily test the value from querySelector and either remove it or issue a message:

  const lastItem = document.querySelector("li:last-child");
  if (lastItem)
    lastItem.remove();        // it's not null, so remove it
    alert("No more items!");  // otherwise alert