read in file

[Chris Daves]

Hi,
I've created a simple program which will read in a file.
#

class Reference
references = 'C:\Documents and Settings\Chris
Davies\Desktop\References.rb'

f = File.open(references, 'r')
file_data = f.read
f.close



puts file_data
end
#

but i want to take this file data and interpret each line of data and
the put each line into a new file line by line.

cheers

 

[Junyoung Kim]

Hi,
I've created a simple program which will read in a file.
#

class Reference
references = 'C:\Documents and Settings\Chris
Davies\Desktop\References.rb'

f = File.open(references, 'r')
file_data = f.read
f.close



puts file_data
end
#

but i want to take this file data and interpret each line of data and
the put each line into a new file line by line.

cheers

File.open("path/your/file") do |sFile|
while sLine = sFile.gets
puts YouCanSeeYourData
end
end

 

[Chris Daves]

File.open("path/your/file") do |sFile|
while sLine = sFile.gets
puts YouCanSeeYourData
end
end

cheers for that, but how can i take that data and move it into a new
file line by line? i just want to move exactly the same data from an
existing file to a new file.

cheers

 

[Junyoung Kim]

if you dont want to modify the existing file, you dont need to open
file. just duplicate it or copy it.

in my case, i will use fileutils(cp_r methods is only available on 1.8)

example)

require 'fileutils'

include FileUtils

cp_r "existing", "new"

 

[Lee Jarvis]

Or if you do want to read and modify it..

new = File.open('filetowriteto', 'w')
File.foreach('oldfile') do |line|
new.puts line
# ...
end

or...

File.open('newfile', 'w') do |file|
file.puts File.read('oldfile')
end

or..

There are many ways, check out File# and FileUtils


Regards,
Lee

 

[Sebastian Hungerecker]

f = File.open(references, 'r')
file_data = f.read
f.close

That can be written as
file_data=File.read("references")
It's generally better not to use File in a way that you have to manually close
the file.

but i want to take this file data and interpret each line of data and
the put each line into a new file line by line.

File.open(outfile, "w") do |of|
File.foreach(infile) do |line|
do_something_with line
of.puts line
end
end


HTH,
Sebastian

 

[Mike McKinney]

[Note: parts of this message were removed to make it a legal post.]

another way...

File.open('out.txt', 'w') do |out|
File.open('test.txt', 'r').each do |line|
out.puts line if (line.size > 4)
end
end

Here are some ways to pull each line from a file in other languages:
http://blog.huikau.com/2007/11/25/simple-file-io-in-different-dynamic-languages/

M

 

[Sebastian Hungerecker]

File.open('out.txt', 'w') do |out|
=A0 File.open('test.txt', 'r').each do |line|
=A0 =A0 out.puts line if (line.size > 4)
=A0 end
end

That leaves test.txt open which is not good. Don't use File.open in chains=
=20
like that. Or better yet: Don't use File.open without a block at all.

HTH,
Sebastian
=2D-=20
NP: Katatonia - Day
Jabber: (e-mail address removed)
ICQ: 205544826

 

[Phrogz]

That leaves test.txt open which is not good. Don't use File.open in chains
like that. Or better yet: Don't use File.open without a block at all.

He is using the block form of File.open, which is guaranteed to close
the file at the end. Right?

 

[Phrogz]

He is using the block form of File.open, which is guaranteed to close
the file at the end. Right?

Nevermind; my reading comprehension seems to be turned off this
morning.

 

[Mike McKinney]

[Note: parts of this message were removed to make it a legal post.]

very good point!