Question

I inject a style via javascript in the head of a document in this way:

var style = document.createElement("style");
document.head.appendChild(style);
style.innerHTML = "a, .left-hand { cursor:wait; }";

I’d like to know if there’s a way to check if this style is in the document (considering that there others) and how to delete it.

Thanks

Answer 1

Just keep the reference around, in this case the style variable.

To check if it’s still in the DOM, check if it has a parent using parentNode. If it does, it’s still in the DOM. If it does not (null), it’s not in the DOM.

To remove it:

if(style.parentNode){                     //check if it has a parent
    style.parentNode.removeChild(style);  //if it does, this is how to remove it
}

Even after this, as long as something still references the style tag, in this case the style variable, you can still reappend it to the DOM. removeChild only removes the element from the DOM, and it does not clear references.