如何将data.frame转换为带有R的xml文件?

时间:2016-02-05 22:48:40

标签: xml r

我有一个简单的data.frame,包含两个变量title和base64。我需要将这个data.frame转换为XML格式。例如,我的数据是什么样的..

str(df)
     'data.frame':  2 obs. of  2 variables:
     $ title  : chr  "Page One" "Page Two"
     $ base64: chr  "Very Long String thats a base64 character" "Very Long String thats a base64 character"
  

dput(DF)       结构(list(page = c(“Page One”,“Page Two”),base64 = c(“非常长的字符串,表示base64字符”,       “非常长的字符串,其中包含base64字符”)),。Name = c(“page”,       “base64”),row.names = 1:2,class =“data.frame”)

我需要输出一个格式看起来像这样的XML文件......

<report type="enchanced">
    <pages>
        <page>
            <title>Page One</title>
            <page> *** long base64 string *** </page>
        </page>
        <page>
            <title>Page Two</title>
            <page> *** long base64 string *** </page>
        </page>
    </pages>
</report>

我一直在试验R中的XML包,甚至发现这个功能似乎应该可行,但我无法弄明白。任何帮助是极大的赞赏。

library(XML)
convertToXML <- function(df,name) {
  xml <- xmlTree("report")
  xml$addNode(name, close=FALSE)
  for (i in 1:nrow(df)) {
    xml$addNode("page", close=FALSE)
    for (j in names(df)) {
      xml$addNode(j, df[i, j])
    }
    xml$closeTag()
  }
  xml$closeTag()
  return(xml)
}

 tr = convertToXML(df,"pages") 
 cat(saveXML(tr$page())) ## suppose to looks good

1 个答案:

答案 0 :(得分:8)

关于this answer,我做

data<- structure(list(page = c("Page One", "Page Two"), base64 = c("Very Long String thats a base64 character", "Very Long String thats a base64 character")), .Names = c("page", "base64"), row.names = 1:2, class = "data.frame")
names(data) <- c("title", "page")

library(XML)
xml <- xmlTree()
# names(xml)
xml$addTag("report", close=FALSE, attrs=c(type="enhanced"))
xml$addTag("pages", close=FALSE)
for (i in 1:nrow(data)) {
    xml$addTag("page", close=FALSE)
    for (j in names(data)) {
        xml$addTag(j, data[i, j])
    }
    xml$closeTag()
}
xml$closeTag()
xml$closeTag()
cat(saveXML(xml))
# <?xml version="1.0"?>
# 
# <report type="enhanced">
#   <pages>
#     <page>
#       <title>Page One</title>
#       <page>Very Long String thats a base64 character</page>
#     </page>
#     <page>
#       <title>Page Two</title>
#       <page>Very Long String thats a base64 character</page>
#     </page>
#   </pages>
# </report>