查了一会,原来是dom4的标准。
interface CharacterData : Node {
[TreatNullAs=EmptyString] attribute DOMString data;
readonly attribute unsigned long length;
DOMString substringData(unsigned long offset, unsigned long count);
void appendData(DOMString data);
void insertData(unsigned long offset, DOMString data);
void deleteData(unsigned long offset, unsigned long count);
void replaceData(unsigned long offset, unsigned long count, DOMString data);
// NEW
void before((Node or DOMString)... nodes);
void after((Node or DOMString)... nodes);
void replace((Node or DOMString)... nodes);
void remove();
};