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Returns the node immediately preceding the specified one in its parent's childNodes list, null if the specified node is the first in that list.


previousNode = node.previousSibling;


// <a><b1 id="b1"/><b2 id="b2"/></a>

alert(document.getElementById("b1").previousSibling); // null
alert(document.getElementById("b2"); // "b1"


Gecko-based browsers insert text nodes into a document to represent whitespace in the source markup. Therefore a node obtained, for example, using Node.firstChild or Node.previousSibling may refer to a whitespace text node rather than the actual element the author intended to get.

See Whitespace in the DOM and W3C DOM 3 FAQ: Why are some Text nodes empty? for more information.

To navigate the opposite way through the child nodes list use Node.nextSibling.


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 Last updated by: Potappo,