使用R语言的正则表达式从HTML页面提取日期

Question

How do I extract just the date in title="11:53 AM - 27 May 2018" using REGEX.

FYI this is from a HTML page. I want to extract all such matches to a list using R language.

My output should be 27 May 2018.

Thanks in advance for your time :)

Answer 1

Figured it out:

rawHTML <- paste(readLines("D:\\practicum\\CSK.html"), collapse="\n")

b<-unlist(str_match_all(rawHTML, '\\d{2} \\w+ 2018'))

Answer 2

Considering you have HTML code of the page in which you want to find the date, the simplest way will be to use regex to find all parts of the code that look like title="11:53 AM - 27 May 2018" Then you can simply again use regex to extract the date from the string. I have written a basic code, you can modify it and use it according to your nee.

first_match <- regexpr(pattern='title\\s*=\\s*"\\d\\d:\\d\\d\\s*(AM|PM)\\s*-\\s*\\d\\d\\s[a-zA-Z]{3}\\s\\d{4}"', str)`
match_str <- regmatches(str,m)
date_exp <- regexpr(pattern='\\d\\d\\s[a-zA-Z]{3}\\s\\d{4}', match_str)
date <- regmatches(match_str, date_exp)

date is your required output and str is the code as string.