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SVGNumberList: insertItemBefore() method - Web APIs | MDN
SVGNumberList: insertItemBefore() method Baseline Widely available
The insertItemBefore()
method of the SVGNumberList
interface inserts a new item into the list at the specified position. The first item is indexed 0. The inserted item is the item itself and not a copy.
If the new item is already in a list, it is removed from its previous list before it is inserted into this list.
If the item is already in this list, note that the index of the item to insert before is before the removal of the item.
If the index is equal to 0, then the new item is inserted at the front of the list.
If the index is greater than or equal to the length
, then the new item is appended to the end of the list.
insertItemBefore(newItem, index)
newItem
The SVGNumber
to add to the list.
index
A non-negative integer that specifies the index of the item to insert the new item before.
DOMException
NoModificationAllowedError
Thrown if the SVGNumberList
corresponds to a read-only attribute or when the object itself is read-only.