On Oct 9, 2006, at 9:13 AM, Li Chen wrote:

> Hi all,
>
> 1) I read lines from a file and put them into one string. There are  
> many
> empty sapces within the string. Which method is used to remove the
> spaces? I try gsub!("\s",'') but it doesn't work. Any help will be
> appreciated.

Try gsub(/\s/, '')

> 2) I read each line from a file and split each of them into several
> fields/segments. Then I need to populate an array with one field only
> from each line. How do I do that? I know do these in Perl but have no
> idea using Ruby.

Would need more information about your code to answer this.

> 3) How do I search help or some methods/predifined variables from ruby
> command prompt? Is it possible to do that? Right now the only thing I
> can do is  to open the folder containing the manual and read them  
> in IE
> browser. Is this the Ruby way?

There's nothing wrong with your way, but there are many other ways to  
get help while coding. Here are two you might consider:

1. visit and download from

    http://ruby.cenophobie.com/rubycheat.php

The Ruby Cheatsheet is especially good for looking up predefined  
variables.

2. Open another terminal window and use ri to get help on classes and  
methods. For example:

     ri gsub

Regards, Morton