Question

尝试解决正则表达式登录问题。以下是规则：

允许的字符为：小写字母，数字，下划线。
长度应在4到16个字符之间。

以下是必须通过的测试用例：

Test.describe("Basic tests") do
  Test.assert_equals(validate_usr('asddsa'), true)
  Test.assert_equals(validate_usr('a'), false)
  Test.assert_equals(validate_usr('Hass'), false)
  Test.assert_equals(validate_usr('Hasd_12assssssasasasasasaasasasasas'), false)
  Test.assert_equals(validate_usr(''), false)
  Test.assert_equals(validate_usr('____'), true)
  Test.assert_equals(validate_usr('012'), false)
  Test.assert_equals(validate_usr('p1pp1'), true)
  Test.assert_equals(validate_usr('asd43 34'), false)
  Test.assert_equals(validate_usr('asd43_34'), true)
end

这是我的代码：

def validate_usr(username)
  if (username.length > 3 && username == username.downcase)
    return true
  elsif
    username.include?(" ") == true
    return false 
  else 
    return false
  end
end

遇到涉及空间的测试用例9的问题。它返回true。

Answer 1

Test case 9 returns true because it satisfies username.length > 3 && username == username.downcase. Note that " ".downcase == " " here.

Move that return false if username.include?(" ") up and it should work. I honestly suggest using Regex though.

def validate_usr(username)
  /\A[a-z0-9_]{4,16}\z/ === username
end

使用正则表达式验证用户名

1 个答案: