Ruby/File Directory/File.new

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File Modes Usable with File.new

File Mode      Properties of the I/O Stream 
r              Read-only. 
r+             Both reading and writing are allowed. 
w              Write-only. A new file is created (or an old one overwritten as if new).
w+             Both reading and writing are allowed, but File.new creates a new file from scratch (or overwrites an old one as if new).
a              Write (in append mode). 
a+             Both reading and writing are allowed (in append mode). The file pointer is placed at the end of the file and writes will make the file longer.
b              Binary file mode (only required on Windows). You can use it in conjunction with any of the other modes listed.



File.new creates a new object of the class File using the method new.

file1 = File.new("Sample", "r")



File.open

file2 = File.open("C:\\Ruby\\Sample"){|f| puts "The file object is #{f}"}
puts file2



Using the append mode to create a program that appends a line of text to a file each time it"s run:

f = File.new("logfile.txt", "a")
f.puts Time.now
f.close



You need to specify the full path for the file unless the file is in the current working directory.

file1 = File.new("Sample", "r")
# Thus the preceding statement should be written as:
file1 = File.new("C:\\Ruby\\Sample", "r")
file1.close