需要澄清 ePub 规范

Question

只是想获得有关 ePub 规范的一些帮助。toc.ncx 是否必须具有 src(即 xhtml)。我观察到 .opf 文件中也提供了相同的内容 src。

Answer 1

是的，这是强制性的，这是一个设计问题:

Overlap between NCX and OPF metadata

Because the NCX is borrowed from another standard, there is some overlap between the information encoded in the NCX and that in the OPF. This is rarely a problem when you generate EPUBs programmatically, where the same code can output to two different files. Take care to put the same information in both places, as different EPUB readers might use the values from one or the other.

Source

在规范的 future 版本 ( ePub 3 ) 中，情况不再如此，但请注意，目前没有设备支持它。