需要ePub规范说明(ePub specifications clarification needed)

需要ePub规范说明(ePub specifications clarification needed)

只是想要一些关于ePub规范的帮助.. toc.ncx是否必须拥有src（即xhtml）。我观察到相同的内容src也可以在.opf文件中使用。

just wanted some help on ePub specifications.. Is it mandatory for the toc.ncx to have the src(ie. the xhtml) .I have observed the same content src is also available in the .opf file.

最满意答案

是的，这是强制性的，这是一个设计问题：

NCX和OPF元数据之间的重叠

由于NCX是从另一个标准借用的，因此NCX中编码的信息与OPF中的信息之间存在一些重叠。 当您以编程方式生成EPUB时，这很少是一个问题，其中相同的代码可以输出到两个不同的文件。 注意在两个地方放置相同的信息，因为不同的EPUB读者可能会使用其中一个或另一个的值。

资源

在未来版本的规范（ ePub 3 ）中不再是这种情况，但请注意，目前没有设备支持它。

Yes, that is mandatory and that's a design problem :

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

That's not the case anymore in the future version of the norm (ePub 3), but please note that no device support it currently.