Name
Node.insertBefore( ) — insert a node into the document tree before the specified node
Availability
DOM Level 1 Core
Synopsis
Node insertBefore(NodenewChild, NoderefChild) throws DOMException;
Arguments
-
newChild The node to be inserted into the tree. If it is a DocumentFragment, its children are inserted instead.
-
refChild The child of this node before which
newChildis to be inserted. If this argument isnull,newChildis inserted as the last child of this node.
Returns
The node that was inserted.
Throws
This method may throw a DOMException with the following
code values:
-
HIERARCHY_REQUEST_ERR This node does not support children, or it does not allow children of the specified type, or
newChildis an ancestor of this node (or is this node itself ).-
WRONG_DOCUMENT_ERR The
ownerDocumentproperty ofnewChildand this node are different.-
NO_MODIFICATION_ALLOWED_ERR This node is read-only and does not allow insertions or the parent of
newChildis read-only and does not allow deletions.-
NOT_FOUND_ERR refChildis not a child of this node.
Description
This method inserts the node newChild into
the document tree as a child of this node. The new node is positioned
within this node’s childNodes[] array so
that it comes immediately before the
refChild node. If
refChild is null,
newChild is inserted at the end of
childNodes[], just as with the
appendChild( ) method. Note that it is illegal to
call this method with a refChild that is
not a child of this node.
If newChild is already in the ...