HTML DOM compareDocumentPosition() Method

MethodThe method is to compare the position of the given node with any other node in any document.

The return value is a bitmask with the following values:

Name	Values
DOCUMENT_POSITION_DISCONNECTED	1
DOCUMENT_POSITION_PRECEDING	2
DOCUMENT_POSITION_FOLLOWING	4
DOCUMENT_POSITION_CONTAINS	8
DOCUMENT_POSITION_CONTAINED_BY	16
DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC	32

Syntax:

node.compareDocumentPosition(node)

示例

Example1　var p1= document.getElementById("p
Example2　var p2= document.getElementById("p
").lastChild;1var x = p2.compareDocumentPosition(p

Browser Compatibility

All browsers fully support the compareDocumentPosition() method:
Method	compareDocumentPosition()	compareDocumentPosition()	compareDocumentPosition()	compareDocumentPosition()	compareDocumentPosition()

Parameter Value	Parameter
Description	node

Technical Details	Return value: A number representing the position between the two nodes. 1Possible return values: 2).Is located before the second node (p1).Is located after the first node (p2).There is no relationship, the two nodes do not belong to the same document. 4).Is located before the second node (p1).Is located after the first node (p2).Is located after the second node (p 8).Is located before the first node (p1).Is located at the second node (p2).Inside. 16).The second node (p2).Is located at the first node (p1).Inside. 32There is no relationship, or two nodes are two attributes on the same element.
DOM Version:	DOM Level1