在chapter_name使用“!expr function(i) paste('第',i,'章',sep='')”可以正常生成“第1章"...，但是我想将阿拉伯数字换成中文的数字，如1换成一。我做了如下尝试：
!expr function(i) paste('第',c('一','二','三','四','五','六','七','八','九','十','十一','十二','十三','十四','十五','十六','十七','十八','十九','二十','二十一','二十二','二十三','二十四','二十五')[i],'章',sep='')
build没有问题，但是所有的章的编号都是“第NA章”。
在console中单独运行这个函数是没有问题的，如下所示：

y <- function(i) paste('第',c('一','二','三','四','五','六','七','八','九','十','十一','十二','十三','十四','十五','十六','十七','十八','十九','二十','二十一','二十二','二十三','二十四','二十五')[i],'章',sep='')
y(25)
[1] "第二十五章"

非常期待并感谢您的解答。

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