ruby - Ruby解析库如何排除非IPv4地址

Question

我想使用Resolv库来解析包括“localhost”在内的主机名，但它也列出了非 IPv4 地址。我想找出第一个 IPv4 地址。看了看图书馆，但找不到这样做的方法。有谁知道这样做的方法，或者我们应该去寻找其他宝石，如 Net:DNS 或 dnsruby？

Answer 1

如果我理解正确，您可以使用Resolv::IPv4::Regexp并Resolv::IPv6::Regexp查看示例：

=> require 'resolv'
=> p Resolv.getaddress "www.ruby-lang.org"
#> "23.23.144.121"
=> ip = "23.23.144.121"
=> ip =~ Resolv::IPv4::Regex
#> 0
=> ip =~ Resolv::IPv6::Regex
#> nil
=> case ip
=> when Resolv::IPv4::Regex
=> puts "It's a valid IPv4 address."
=> when Resolv::IPv6::Regex
=> puts "It's a valid IPv6 address."
=> else
=> puts "It's not a valid IP address."
=> end
#> It's a valid IPv4 address.