HTML DOM compareDocumentPosition method
Examples
Compare the current document location field with the specified field:
var p2=document.getElementById("p2");
p1.compareDocumentPosition(p2);
Output:
try it"
Definition and Usage
compareDocumentPosition () method in document order, compare the current node and document location specified node.
See the example above, the return value might be:
1: There is no relationship between these two nodes do not belong to the same document.
2: the first point (P1) located after the second node (P2).
4: the first point (P1) positioned at the second node (P2) before.
8: the first point (P1) located in the second node (P2).
16: the second node (P2) located within the first node (P1).
32: There is no relationship, or two nodes in the two attributes of the same element.
Note: The return value can be a combination. That means that in 20 Back P1 P2 and P1 (16) positioned at P2 (4) above.
Browser Support
All major browsers support compareDocumentPosition () method
Note: Internet Explorer 8 and earlier versions of IE does not support this method.
grammar
parameter
| 参数 | 类型 | 描述 |
|---|---|---|
| node | Node object | 必须。你想比较的指定节点。 |
return value
| 类型 | 描述 |
|---|---|
| Number | 比较当前节点与指定节点的文档位置
可能的返回值： 查看以上实例，返回值可能是： 1：没有关系，这两个节点不属于同一个文档。 2： 第一节点（P1）位于第二个节点后（P2）。 4：第一节点（P1）定位在第二节点（P2）前。 8： 第一节点（P1）位于第二节点内（P2）。 16： 第二节点（P2）位于第一节点内（P1）。 32:没有关系的，或是两个节点在同一元素的两个属性。 |
technical details
| DOM version | Core Level 1 Node Object |
|---|