返回在Ruby中没有给定符号的行

Question

I want to print the lines from a website's content page which do not start with the symbol "#" .

def open(url)
  Net::HTTP.get(URI.parse(url))
end

page_content = open('https://virusshare.com/hashes/VirusShare_00000.md5')

line_num=0
page_content.each_line do |lines|
  line_num += 1
  if lines[0] == "#"
    lines.each_line do |line|
      if (line_num==1)
        puts line
      end
    end
  end
end

Expected result:

2d75cc1bf8e57872781f9cd04a529256
00f538c3d410822e241486ca061a57ee
3f066dd1f1da052248aed5abc4a0c6a1
781770fda3bd3236d0ab8274577dddde
................................

It works when I try to print the lines that start with "#" :

lines[0] != "#"

But it does not work in the opposite way.

Answer 1

You could just use a mix of reject and start_with? :

require 'net/http'
def open(url)
  Net::HTTP.get(URI.parse(url))
end

page_content = open('https://virusshare.com/hashes/VirusShare_00000.md5')

puts page_content.each_line.reject{ |line| line.start_with?('#') }

It outputs :

2d75cc1bf8e57872781f9cd04a529256
00f538c3d410822e241486ca061a57ee
3f066dd1f1da052248aed5abc4a0c6a1
781770fda3bd3236d0ab8274577dddde
86b6c59aa48a69e16d3313d982791398
42914d6d213a20a2684064be5c80ffa9
10699ac57f1cf851ae144ebce42fa587
248338632580f9c018c4d8f8d9c6c408
999eb1840c209aa70a84c5cf64909e5f
12c4201fe1db96a1a1711790b52a3cf9
................................

If you just want the first line :

page_content.each_line.find{ |line| !line.start_with?('#') }

Notes

page_content.each_line do |lines|

lines should be called line . It is just one line.

When you call

lines.each_line do |line|

You iterate over "each" line of just one line, so the loop isn't needed at all.

Your code could be :

require 'net/http'

def open(url)
  Net::HTTP.get(URI.parse(url))
end

page_content = open('https://virusshare.com/hashes/VirusShare_00000.md5')

page_content.each_line do |line|
  puts line if line[0] != "#"
end