我无法增加字符串包含整数值？

Question

如何根据最后一个整数增加最后一个字符串？例如。＆＃34; foo＆＃34; =＆＃34; f001＆＃34;， ＆＃34; foo9＆＃34; =＆＃34; foo10＆＃34;，＆＃34; foo99＆＃34; =＆＃34; foo100＆＃34;，＆＃34; foo001＆＃34; =＆＃34; foo002＆＃34;

Answer 1

你可以做到这一点......

def increment_string(string)
  old_digits = string.scan(/\d+$/).first || ''
  string.sub(/\d+$/,'') + (old_digits.to_i+1).to_s.rjust(old_digits.size, '0')
end

p increment_string("beep")
=> "beep1"

p increment_string("beep5")
=> "beep6"

p increment_string("beep99")
=> "beep100"

p increment_string("beep004")
=> "beep005"