2 编辑、预览和发布

2.1 bookdown源码组成

bookdown的源文件由下列格式组成 - .rmd - .yml

2.1.1 .rmd文件

rmd为章节的源文件。主要包括 - index.rmd - 其他章节的rmd

index.rmd相当于是主页文件，bookdown在渲染的时候将index放在最前面，其他章节则默认按照数字编号排列。 因此一般章节的命名为:01-a,02-aa,…。 如果不想按照数字排列，则需要新建_bookdown.yml文件来指定渲染顺序 参考第2.1.2小节。

index.rmd的开始可以放YMAL的数据，以---开始和结束。比如说

--- 
title: "Advanced R Solutions"   <!-- 标题. -->
author: "Malte Grosser & Henning Bumann" <!-- 作者. -->
date: "2017-01-30"   <!-- 日期. -->
knit: "bookdown::render_book" 
site: bookdown::bookdown_site <!--  RStudio will be able to discover the directory as a book source directory，在Rstudio打开project就能build了. -->
output: <!---输出格式，也可以新建一个.output.yml在.yml里设置--->
  bookdown::gitbook:
    config:
      toc:
          collapse: section
          scroll_highlight: yes
          before: null
          after: null
      edit: https://github.com/Tazinho/Advanced-R-Solutions/edit/master/%s
documentclass: book
bibliography: [packages.bib] <!--bib文件的名字. -->
biblio-style: apalike <!--文献显示的格式. -->
link-citations: yes
github-repo: Tazinho/Advanced-R-Solutions <!--github仓库的网址 -->
before_chapter_script: ["before_chapter_script_1.R"]
description: "Solutions to the exercises in Hadley Wickham's book Advanced R."
cover-image: images/advrs_cover.png   <!--封皮图像-->
---

2.1.2 .yml

• _bookdown.yml (可选)

_bookdown.yml里的rmd_files可以指定渲染的顺序，比如：

rmd_files: ["index.RMD", "01-install_bookdown.Rmd", "03-edit-preview-publish.Rmd","02-test_syntax.rmd"]

_bookdown.yml还可以包含其他信息，比如

book_filename: "my-book.Rmd"
repo: https://github.com/rstudio/bookdown/
before_chapter_script: ["script1.R", "script2.R"]
after_chapter_script: "script3.R"
edit: https://github.com/rstudio/bookdown-demo/edit/master/%s
output_dir: "book-output" # 渲染后的目录名字
clean: ["my-book.bbl", "R-packages.bib"]
language:
  label:
    fig: "FIGURE "
    tab: "TABLE "
  ui:
    edit: "Edit"
    chapter_name: "Chapter "

含义可以参考：bookdown书籍