Ruby-on-rails 仅在创建和更新时验证 Rails 模型
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Rails model validation on create and update only
提问by Jakub Arnold
If I want to have validation only on create, then I can do
如果我只想在创建时进行验证，那么我可以做
validates_presence_of :password, :on => :create
But how do I say on create and update? I tried this but it didn't work:
但是我怎么说创建和更新？我试过这个，但没有用：
validates_presence_of :password, :on => [ :create, :update ]
Do I have to define the validation two times?
我必须定义两次验证吗？
回答by Alessandra Pereyra
By default, the validations run for both create and update. So it should be just:
默认情况下，验证同时针对创建和更新运行。所以它应该只是：
validates_presence_of :password
The :on key just allows you to choose one of them.
:on 键只允许您选择其中之一。
回答by FJ.
Only write:
只写：
validates_presence_of :password
No need...
不需要...
on => :create
回答by Ederson Badeca
You can use this when you need to disable the validation on some specific operations, such as delete.
当您需要禁用某些特定操作（例如删除）的验证时，您可以使用它。
