使用Regex验证密码

Question

我正在开发一个需要根据以下条件验证密码的Rails 3应用程序: must be at least 6 characters and include one number and one letter.

这是我的正则表达式:

validates :password, :format => {:with => /^[([a-z]|[A-Z])0-9_-]{6,40}$/, message: "must be at least 6 characters and include one number and one letter."}

现在,如果我输入密码(例如:dogfood)它将通过.但我需要做的是通过上述标准.

我在正则表达式方面并不是那么出色,所以非常感谢任何帮助!

Answer 1

使用前瞻断言:

/^(?=.*[a-zA-Z])(?=.*[0-9]).{6,}$/
  |             |          |
  |             |          |
  |             |          Ensure there are at least 6 characters.
  |             |
  |             Look ahead for an arbitrary string followed by a number.
  |                        
  Look ahead for an arbitrary string followed by a letter.

从技术上讲,在这种情况下你不需要锚,但使用它们是个好习惯.