Node: firstChild property
{{APIRef("DOM")}}
The read-only firstChild property of the {{domxref("Node")}} interface
returns the node’s first child in the tree,
or null if the node has no children.
If the node is a {{domxref("Document")}} ,
this property returns the first node in the list of its direct children.
[!NOTE] This property returns any type of node that is the first child of this one. It may be a
{{domxref("Text")}}or a{{domxref("Comment")}}node. If you want to get the first{{domxref("Element")}}that is a child of another element, consider using{{domxref("Element.firstElementChild")}}.
Value
A {{domxref("Node")}} , or null if there are none.
Example
This example demonstrates the use of firstChild and how whitespace nodes
might interfere with using this property.
<p id="para-01">
<span>First span</span>
</p>
const p01 = document.getElementById("para-01");
console.log(p01.firstChild.nodeName);
In the above, the console will show ‘#text’
because a text node is inserted to maintain the whitespace between the end of the
opening <p> and <span> tags. Any
whitespace
will create a #text node, from a single space to multiple spaces, returns,
tabs, and so on.
Another #text node is inserted between the closing
</span> and </p> tags.
If this whitespace is removed from the source, the #text nodes are not inserted and the span element becomes the paragraph’s first child.
<p id="para-01"><span>First span</span></p>
const p01 = document.getElementById("para-01");
console.log(p01.firstChild.nodeName);
Now the console will show ‘SPAN’.
To avoid the issue with node.firstChild returning #text or
#comment nodes, {{domxref("Element.firstElementChild")}} can be used to
return only the first element node.
Specifications
{{Specifications}}
Browser compatibility
{{Compat}}
See also
{{domxref("Element.firstElementChild")}}{{domxref("Node.lastChild")}}