Ruby on Rails - 验证成本
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Ruby on Rails - Validate a Cost
提问by freshest
What is the best way to validate a cost/price input by a user, validation rules below:
验证用户输入的成本/价格的最佳方法是什么，验证规则如下：
- Examples of formats allowed .23, .2, 1.23, 0.25, 5, 6.3 (maximum of two digits after decimal point)
- Minimum value of 0.01
- Maximum value of 9.99
- 允许的格式示例 .23、.2、1.23、0.25、5、6.3（小数点后最多两位）
- 最小值 0.01
- 最大值 9.99
回答by rwilliams
Check the price and verify the format
检查价格并验证格式
#rails 3
validates :price, :format => { :with => /\A\d+(?:\.\d{0,2})?\z/ }, :numericality => {:greater_than => 0, :less_than => 10}
#rails 2
validates_numericality_of :price, :greater_than => 0, :less_than => 10
validates_format_of :price, :with => /\A\d+(?:\.\d{0,2})?\z/
回答by jpemberthy
For client side validations you can use a jQuery plugin like this onethat allows you to define different valid formats for a given input.
对于客户端验证，您可以使用像这样的 jQuery 插件，它允许您为给定的输入定义不同的有效格式。
For server side validations and according to this question/answermaybe you should use a decimalcolumn for pricein which you can define values for precisionand scale, scalesolves the two digits after decimal point restriction.
对于服务器端验证，根据此问题/答案，您可能应该使用一decimal列price，您可以在其中定义precision和的值scale，scale解决小数点限制后的两位数。
Then to validate the numericality, minimum and maximum value you can use the next validation method:
然后要验证数值、最小值和最大值，您可以使用下一个验证方法：
validates_numericality_of :price, :greater_than => 0, :less_than => 10
回答by Shreyas
You can build custom validations.Lets say, for example the second case:
您可以构建自定义验证。让我们说，例如第二种情况：
validate :price_has_to_be_greater_than_minimum
def price_has_to_be_greater_than_minimum
errors.add(:price, "price has to be greater than 0.01") if
!price.blank? and price > 0.01
end
More on this, in the Rails Guides, here.
更多关于这方面的信息，在 Rails 指南中，这里。
