.split和Ruby中的正则表达式

Question

I want to split my string by (',') but ignore ',' if they are inside quotes. For example

 " 2,2,4,'hello', 'world', 'hi, there' " 

I want to split it so 'hi, there' will not be split into two different array elements in ruby. How can I do that? Probably use some regex?

EDIT: IF I use this, (from link to possible dublicate)

 values = values.split(',(?=([^\\"]*\\"[^\\"]*\\")*[^\\"]*$)', -1) 

my string is split correctly, but now I can not use .delete_at() method on my array. Before I could do:

 values.delete_at(20) 

Answer 1

Very well. Taking inspiration from this answer , the regular expression you are looking for is:

values.split(/,(?=(?:[^']*'[^']*')*[^']*$)/)

This will not work if you have escaped quotes, for example ( eg "'O\\'Reilly\\'s car'" ).

However, this looks a bit like an XY problem. If you want to parse CSV, as it seems, and if this was a compliant CSV, you could use CSV.parse or CSV.parse_line . It is not, due to extra spaces between column separators. Using standard formats and standard parsers is, if possible, almost always preferable to home-grown solutions.

Answer 2

Here's a non-regex solution:

str = " 2,2,4,'hello', 'world', 'hi, there' "

first_quote_read = false 
str.each_char.with_object (['']) do |c,a|
  if c == ?, && !first_quote_read
    a << ''
  else
    a[-1] << c
    first_quote_read = !first_quote_read if c == ?'      
  end
end
  #=> [" 2", "2", "4", "'hello'", " 'world'", " 'hi, there' "]