How to create a file in Ruby

Question

I\'m trying to create a new file and things don\'t seem to be working as I expect them too. Here\'s what I\'ve tried:

File.new \"out.txt\"
File.open \"out.tx         


        

Answer 1

data = 'data you want inside the file'.

You can use File.write('name of file here', data)

Answer 2

Use:

File.open("out.txt", [your-option-string]) {|f| f.write("write your stuff here") }

where your options are:

• r - Read only. The file must exist.
• w - Create an empty file for writing.
• a - Append to a file.The file is created if it does not exist.
• r+ - Open a file for update both reading and writing. The file must exist.
• w+ - Create an empty file for both reading and writing.
• a+ - Open a file for reading and appending. The file is created if it does not exist.

In your case, 'w' is preferable.

OR you could have:

out_file = File.new("out.txt", "w")
#...
out_file.puts("write your stuff here")
#...
out_file.close

Answer 3

OK, now I feel stupid. The first two definitely do not work but the second two do. Not sure how I convinced my self that I had tried them. Sorry for wasting everyone's time.

In case this helps anyone else, this can occur when you are trying to make a new file in a directory that does not exist.

Answer 4

You can also use constants instead of strings to specify the mode you want. The benefit is if you make a typo in a constant name, your program will raise an runtime exception.

The constants are File::RDONLY or File::WRONLY or File::CREAT. You can also combine them if you like.

Full description of file open modes on ruby-doc.org

Answer 5

Try

File.open("out.txt", "w") do |f|     
  f.write(data_you_want_to_write)   
end

without using the

File.new "out.txt"

Answer 6

Try using "w+" as the write mode instead of just "w":

File.open("out.txt", "w+") { |file| file.write("boo!") }