This function returns a new instance of class DomEntityReference. The content of the entity reference is the value of the passed parameter. 本节点不会出现在文档中，除非是用例如 domnode_append_child() 来插入的。
The return value is FALSE if an error occurred.
See also domnode_append_child(), domdocument_create_element(), domdocument_create_text(), domdocument_create_cdata_section(), domdocument_create_processing_instruction(), domdocument_create_attribute(), and domnode_insert_before().