如何使用Ruby匹配较长字符串中以'H‘开头的10个字符的子字符串？

Question

我有以下字符串：

/Users/patelc75/Documents/code/haloror/dialup/H200000787_1313406125/H200000787_1313389058_1.xml

在Ruby中，如何提取以字母H开头并在H之后包含9个数字(仅数字)的前10字符子字符串。在上面的示例中，子字符串将为H200000787

Answer 1

您需要的是String#[]方法：

str = '/Users/patelc75/Documents/code/haloror/dialup/H200000787_1313406125/H200000787_1313389058_1.xml'

puts str[/H\d{9}/]     #=> H200000787

Answer 2

irb(main):001:0> s = "/Users/patelc75/Documents/code/haloror/dialup/H200000787_1313406125/H200000787_1313389058_1.xml"
=> "/Users/patelc75/Documents/code/haloror/dialup/H200000787_1313406125/H200000787_1313389058_1.xml"
irb(main):002:0> s =~ /H\d{9}/
=> 46
irb(main):003:0> $&
=> "H200000787"