The insertItemBefore() method of the SVGStringList 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.
length, then the new item is appended to the end of the list.insertItemBefore(newItem, index)newItemThe string to add to the list.
indexA non-negative integer that specifies the index of the item to insert the new item before.
The string that was added to the list.
NoModificationAllowedError DOMExceptionThrown if the SVGStringList corresponds to a read-only attribute or when the object itself is read-only.