How to extract text from a several “div class” (html) using R?

Question

My goal is to extract info from this html page to create a database: https://drive.google.com/folderview?id=0B0aGd85uKFDyOS1XTTc2QnNjRmc&usp=sharing

One of the varia

Answer 1

There are lots of ways to do this, and depending on how consistent the HTML is, one may be better than another. A reasonably simple strategy that works in this case, though:

library(rvest)

page <- read_html('page.html')

# find all nodes with a class of "listing_row_price"
listings <- html_nodes(page, css = '.listing_row_price')

# for each listing, if it has two children get the text of the first, else return NA
prices <- sapply(listings, function(x){ifelse(length(html_children(x)) == 2, 
                                              html_text(html_children(x)[1]), 
                                              NA)})
# replace everything that's not a number with nothing, and turn it into an integer
prices <- as.integer(gsub('[^0-9]', '', prices))