I'm having a bit of trouble searching through a file and editing certain parameters of the file. The code is below
file_names = ["#{fileNameFromUser}"]
file_names.each do |file_name|
text = File.read(file_name)
replacedcontent = text.gsub(/textToReplace/, "#{ReplaceWithThis}")
replacedcontent += text.gsub(/textToReplace2/, "#{ReplaceWithThis2}")
# To write changes to the file, use:
File.open(file_name, "w") {|file| file.puts replacedcontent}
end
so right now what it does is that it print the contents of the file twice and I can only assume its because its inside the do loop. My end goal here is that the file has textToReplace and textToReplace2 and I need it to read through the file, replaced both with whatever the user inputs and save/write changes to the file.
it print the contents of the file twice and I can only assume its because its inside the do loop
Nope, it's because you append it twice:
text = first_replacement_result
text += second_replacement_result
There's two ways to do this: one with mutation:
text.gsub!(...) # first replacement that changes `text`
text.gsub!(...) # second replacement that changes `text` again
or chained replacement:
replacedcontent = text.gsub(...).gsub(...) # two replacements one after another
You will need to re-use replacedcontent instead of concatenating it to avoid printing it twice.
file_names = ["#{fileNameFromUser}"]
file_names.each do |file_name|
text = File.read(file_name)
replacedcontent = text.gsub(/textToReplace/, "#{ReplaceWithThis}")
replacedcontent = replacedcontent.gsub(/textToReplace2/, "#{ReplaceWithThis2}")
# To write changes to the file, use:
File.open(file_name, "w") {|file| file.puts replacedcontent}
end
OR
replacedcontent = text.gsub(/textToReplace/, "#{ReplaceWithThis}").gsub(/textToReplace2/, "#{ReplaceWithThis2}")
Related
I've got a list of devices:
ipc-bei640-r-br-01
ipc-bei640-r-br-02
ipc-bei640-r-br-03
ipc-bei640-r-br-04
ipc-bei640-r-br-05
ipc-bem640-r-br-01
ipc-bem640-r-br-02
ipc-bem640-r-br-03
ipc-crg660-r-br-02
ipc-geb680-r-br-04
ipc-lgv630-r-br-01
This small little ruby script counts the lines of the file braslist.txt scans it with a regex and writes the results to a newfile called "strippedfile.txt"
lines = IO.readlines("/usr/local/bin/braslist.txt")
# Linecount is forwarded to StdOut.
puts lines.length
str = File.read('braslist.txt')
file_name = ['strippedfile.txt']
file_name.each do |file_name|
text = File.read(file_name)
new_contents = str.scan(/^ipc-(?<bng>[a-z]{3}\d{3})-r-br(?<nr>-\d{2})$/)
# open and write to a file with ruby
open('strippedfile.txt', 'w') { |f|
f.print new_contents
}
end
Now what i cant seem to fix, is in the new file "strippedfile" the results are always ["bei640", "-01"] ["bei640", "-02"] ["bei640", "-03"]
And i am trying to get all results in this format:
bei640-01
bei640-02
bei640-03
bei640-04
scan returns an array of matches, you probably want to join them:
- new_contents = str.scan(/^ipc-(?<bng>[a-z]{3}\d{3})-r-br(?<nr>-\d{2})$/)
+ new_contents = str.scan(/^ipc-(?<bng>[a-z]{3}\d{3})-r-br(?<nr>-\d{2})$/).map(&:join)
To print everything without quotes and brackets line by line:
- f.print new_contents
+ f.puts new_contents
Assuming your resultant array is
a = [["bei640", "-02"], ["bei640", "-03"]]
You can use join to get your desired result
a.map{|i| i.join } #=> ["bei640-02", "bei640-03"]
or use shortcut as mudasobwa answered
a.map(&:join) #=> ["bei640-02", "bei640-03"]
I am trying to recursively replace a whole line from index.html files into a directory with sub-directories.
The code above puts the right lines I'm searching with the var "pattern", but when I run it, it removes everything form my index.html files.
pattern = "Keyword"
replacement = "<td width=\"30\"><img src=\"styles/img/trans.gif\" width=\"30\"></td>"
Dir.glob('/Users/root/Desktop/directory/test/**/index.html') do |item|
next unless File.file?(item)
File.open(item, "w+:ASCII-8BIT") do |f|
f.each_line do |line|
if line.match(pattern)
my_line = line
line.sub(my_line, replacement)
end
end
end
end
What am I doing wrong ?
You need to read the file first, build the expected output, and then write it:
Dir.glob('/Users/root/Desktop/directory/test/**/index.html') do |item|
next unless File.file?(item)
output = IO.readlines(item).map do |line|
if line.match(pattern)
replacement
else
line
end
end
File.open(item, "w+:ASCII-8BIT") do |f|
f.write output.join
end
end
end
You use File.open with open mode w+ which, according to Ruby documentation, is:
"w+" Read-write, truncates existing file to zero length or creates a new file for reading and writing.
To read the file and put some lines use r:
File.open(item, "r:ASCII-8BIT")
Below is the piece of code that is supposed read the directory and for each file entry prints the first row of the file. The issue is x is not visible so file is not being parsed.
Dir.foreach("C:/fileload/src") do |file_name|
x = file_name
puts x
f = File.open("C:/fileload/src/" +x)
f.readlines[1..1].each do |line|
puts line
end
end
Why are you assigning x to file_name? You can use file_name directly. And if you are only reading the first line of the file, why not try this?
#!/usr/bin/ruby
dir = "C:/fileload/src"
Dir.foreach(dir) do |file_name|
full = File.join(dir, file_name)
if File.file?(full)
f = File.open(full)
puts f.first
f.close
end
end
You should use File.join to safely combine paths in Ruby. I also checked that you are opening a file using the File.file? method.
You have no visibility issue with x. You should be using File::join or Pathname#+ to build your file paths. You should exclude non-files from consideration. You're selecting the second line, not the first with [1..1]. Here's a cleaner correct replacement for your sample code.
dir = "C:/fileload/src"
Dir.foreach(dir).
map { |fn| File.join(dir,fn) }.
select { |fn| File.file?(fn) }.
each { |fn| puts File.readlines(fn).first }
Here's my code..
require "open-uri"
base_url = "http://en.wikipedia.org/wiki"
(1..5).each do |x|
# sets up the url
full_url = base_url + "/" + x.to_s
# reads the url
read_page = open(full_url).read
# saves the contents to a file and closes it
local_file = "my_copy_of-" + x.to_s + ".html"
file = open(local_file,"w")
file.write(read_page)
file.close
# open a file to store all entrys in
combined_numbers = open("numbers.html", "w")
entrys = open(local_file, "r")
combined_numbers.write(entrys.read)
entrys.close
combined_numbers.close
end
As you can see. It basically scrapes the contents of the wikipedia articles 1 through 5 and then attempts to combine them nto a single file called numbers.html.
It does the first bit right. But when it gets to the second. It only seem's to write in the contents of the fifth article in the loop.
I can't see where im going wrong though. Any help?
You chose the wrong mode when opening your summary file. "w" overwrites existing files while "a" appends to existing files.
So use this to get your code working:
combined_numbers = open("numbers.html", "a")
Otherwise with each pass of the loop the file contents of numbers.html are overwritten with the current article.
Besides I think you should use the contents in read_page to write to numbers.html instead of reading them back in from your freshly written file:
require "open-uri"
(1..5).each do |x|
# set up and read url
url = "http://en.wikipedia.org/wiki/#{x.to_s}"
article = open(url).read
# saves current article to a file
# (only possible with 1.9.x use open too if on 1.8.x)
IO.write("my_copy_of-#{x.to_s}.html", article)
# add current article to summary file
open("numbers.html", "a") do |f|
f.write(article)
end
end
The following code is a line in an xml file:
<appId>455360226</appId>
How can I replace the number between the 2 tags with another number using ruby?
There is no possibility to modify a file content in one step (at least none I know, when the file size would change).
You have to read the file and store the modified text in another file.
replace="100"
infile = "xmlfile_in"
outfile = "xmlfile_out"
File.open(outfile, 'w') do |out|
out << File.open(infile).read.gsub(/<appId>\d+<\/appId>/, "<appId>#{replace}</appId>")
end
Or you read the file content to memory and afterwords you overwrite the file with the modified content:
replace="100"
filename = "xmlfile_in"
outdata = File.read(filename).gsub(/<appId>\d+<\/appId>/, "<appId>#{replace}</appId>")
File.open(filename, 'w') do |out|
out << outdata
end
(Hope it works, the code is not tested)
You can do it in one line like this:
IO.write(filepath, File.open(filepath) {|f| f.read.gsub(//<appId>\d+<\/appId>/, "<appId>42</appId>"/)})
IO.write truncates the given file by default, so if you read the text first, perform the regex String.gsub and return the resulting string using File.open in block mode, it will replace the file's content in one fell swoop.
I like the way this reads, but it can be written in multiple lines too of course:
IO.write(filepath, File.open(filepath) do |f|
f.read.gsub(//<appId>\d+<\/appId>/, "<appId>42</appId>"/)
end
)
replace="100"
File.open("xmlfile").each do |line|
if line[/<appId>/ ]
line.sub!(/<appId>\d+<\/appId>/, "<appId>#{replace}</appId>")
end
puts line
end
The right way is to use an XML parsing tool, and example of which is XmlSimple.
You did tag your question with regex. If you really must do it with a regex then
s = "Blah blah <appId>455360226</appId> blah"
s.sub(/<appId>\d+<\/appId>/, "<appId>42</appId>")
is an illustration of the kind of thing you can do but shouldn't.