Ruby on rails 如何从表单传递值以进行验证

我正在使用RubyonRails创建一个直接借记的表单

我已经设置了表单，并设置了一些基本验证，以确保所有字段都已填写

接下来我想设置一些验证来检查IBAN（国际银行账号）号码是否是有效的IBAN

这涉及到操作字符串、将其转换为数字和做一些数学运算的几个步骤，所有这些我都为其编写了一个方法

我的问题是，我似乎无法将IBAN传递到方法中进行验证

我的确认：

class DirectDebit < ActiveRecord::Base
attr_accessible :address, :amount, :bank_branch, :bic, :date_for_payment, :email, :iban, :name, :name_of_account, :phone

validates :address, :bank_branch, :bic, :date_for_payment, :email, :name, :name_of_account, :phone, presence: true

validates :amount, numericality: {greater_than_or_equal_to: 0.01}

validate :iban 

def iban

    ## Converts all letters in 'number' to uppercase and removes any spaces and anything else that isn't a letter, number or underscore
    iban = iban.upcase.scan(/\w/).join

    ## removes any underscores as ".scan(/\w/)" above reads in letters digits and underscores.
    iban = iban.gsub(/_/, '')

    ## Calculates the length of 'number'
    iban_length = iban.length

    ## Saves the first two letters in 'number' as 'country'
    country = iban.scan(/\A../).join

    ## Checks if the length is correct for the country
    length_correct_for_country = true

    case country
        when "IE"
            if iban_length == 22
                length_correct_for_country = true
            else
                length_correct_for_country = false      
            end
        when "AL"
            if iban_length == 28
                length_correct_for_country = true
            else
                length_correct_for_country = false      
            end
        ...
        when "GB"
            if iban_length == 22
                length_correct_for_country = true
            else
                length_correct_for_country = false      
            end
        when "VG"
            if iban_length == 24
                length_correct_for_country = true
            else
                length_correct_for_country = false      
            end
    end

    ## Identifies what the first 4 characters are, and removes them from the rest of the number
    first_four_characters = iban.slice!(0..3)

    ## Adds the first four characters to the end of the rest
    reordered_number = iban + first_four_characters

    ## Set up an array and have each character in the reordered number read into it, changing it to the appropriate number if it is a letter.
    letters_removed = []
    reordered_number.scan(/./) do |character|
        case character
        when "A"
            letters_removed << 10
        ...
        when "9"
            letters_removed <<9
        end
    end

    ## Change the array to a String and then to a number
    letters_removed = letters_removed.join.to_i

    ## Check to see if it gives a remainder of one when divided by 97
    remainder = letters_removed % 97

    ## Output that it is a valid number if the remainder when it is divided by 97 is 1 and if it is the correct length for the country.
    if remainder == 1 && length_correct_for_country

    else
        remainder = remainder.to_s
        errors.add(:iban, " That is not a valid IBAN. The IBAN that is being supplied is: " + special)
    end

end

end

class DirectDebit
class YourModel < ActiveRecord::Base

  validate :your_method


  def your_method
    #your stuff should return true or false        
  end

end

classyourmodel

希望它能有所帮助。
在您的模型中，iban已经是一种方法，因为它是一个数据库列。因此，您需要执行以下操作：

validate :valid_iban?

def valid_iban?
  ## all of your current validation iban goes here
end

如果您希望能够验证模型的iban以及可能的其他iban：

app/models/validates_iban.rb

class ValidatesIban
  def self.valid?(iban)
    ## all your validation goes here
  end
end

在您的模型中：

validate :valid_iban?

def valid_iban?
  unless ValidatesIban.valid?(iban)
    self.errors(:iban, "is not valid")
  end
end

ValidatesIban方法的好的一面是：您可以在其他地方重用。
我想这一部分已经介绍得很好了，但我想添加一些其他选项：

你可以使用gem'iban tools'
此外，对于（SEPA）直接借记表单/协议，请尝试此SEPA_king gem，它还可以验证BIC和债权人标识符（您可以看到，在IBAN内部，它还使用IBAN工具）
干杯
 这是我的一个基本版本。我做了，有两个长的重复部分，我从中间剪下，用刚刚读过的行替换…返回真或假不是问题，没有什么是通过测试的，因此每次我都有效地得到假，除非我硬编码一个将验证为true的IBAN。请将您的方法名称更改为其他名称。在第一行中，请尝试
IBAN=self.IBAN.upcase.scan（/\w/）.join
。另外，如果您不确定该值是多少，请使用debugger或仅将
Rails.logger.info“*”*50；Rails.logger.info[：iban\u after\u smth，iban].inspect
谢谢，ValidateBan方法在我对它做了一点修改后就起了作用。