JavaScript: Removing DOM Elements
Creating and modifying DOM elements is a fundamental aspect of JavaScript programming. In this context, a common task is to check for the existence of an element, and create it if it does not exist, or remove it if it already does.
Checking for Element Existence
The code provided successfully checks for the presence of an iframe with the ID "injected_frame" using document.getElementById("injected_frame"). If the iframe exists, it evaluates to a non-null reference.
Creating an Element
The code snippet demonstrates the creation of an iframe element with the desired attributes. This involves setting the "id", "src", "width", and "height" attributes using setAttribute(), and then appending the new element to the DOM using appendChild().
Deleting an Element
However, the issue arises when attempting to remove the iframe if it already exists. The code invokes iframe.removeChild(frameid.childNodes[0]), which is incorrect. In JavaScript, the removeChild() method should be applied to the parent element of the element to be removed.
Corrected Code
The corrected code for removing the iframe should be:
<code class="javascript">if (frameid) { frameid.parentNode.removeChild(frameid); }</code>
This ensures that the iframe element with the ID "injected_frame" is successfully removed from the DOM if it exists.
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