分为内部实体与外部实体
内部实体
语法
<!ENTITY entity-name "entity-value"> |
Example
DTD Example: <!ENTITY writer "Donald Duck."> <!ENTITY copyright "Copyright W3Schools."> XML example: <author>&writer;©right;</author> |
注:实体分为三部分:&符 ,实体名字,分号;
外部实体
语法
<!ENTITY entity-name SYSTEM "URI/URL"> |
Example
DTD Example: <!ENTITY writer SYSTEM "http://www.w3schools.com/entities.dtd"> <!ENTITY copyright SYSTEM "http://www.w3schools.com/entities.dtd"> XML example: <author>&writer;©right;</author> |