Hi,

Could any one explain file handling in Ruby?

__________________
Shaalini.S
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Creating a new file.The new and open methods

A new file is created by using the "new" method on the File class.
file = File.new("myfile", "rw")
# ... operations to be done on file
file.close

In the sample above, a file named "myfile" is created with read/write permissions assigned.This will allow you to read from the file or write into it.You should note that in case of a raised exception while processing the file, file.close may not happen as planned, but later along the way,in the meantime holding onto the allocated resources.

Alternatively, you can use the "open" method which is very similar to the "new" one, except:in case a block is associated with the method call, instead of returning the new object, it invokes the block, passing the newly opened File as a parameter.The file is closed when the block exits. In the case of using the "open" method, if an exception is raised inside a block, the file is closed before the exception propagates to the caller.

file = File.open("myfile", "rw")
# ... operations to be done on file
file.close

Reading/writing to files

The gets method

File.open("myfile") do |file|
while content = file.gets
# ... operations on file
end
end

This code reads from the file as long as there is "something" in the file, note the "while content = file.gets" line.

The each_byte method

To be used when you need to process each character in an expression.Here's a sample:

"Sample code".each_byte {|b| puts b.chr}
Obviously, it can be used on files also, to read characters and process sequentially.

File.open("myfile") do |file|
file.each_byte {....}
end

The each_line method

Similar to each_byte, read one line at a time.