在 Rails 中，在两种情况下都执行块: first_or_create [英] In Rails, execute block for both conditions: first_or_create

问题描述

有人知道可以让我查找现有记录或创建新记录并执行后续代码块的 Rails 方法吗?

Anybody know a Rails method that will allow me to look for an existing record or create a new one AND execute a subsequent block of code?

示例:

Model.where(parameters).first_or_create do |m|
  # execute this regardless of whether record exists or not
end

同样，find_or_create_by 方法在任何一种情况下都不执行块.

Similarly, the method find_or_create_by does not execute a block in either scenario.

我可以使用 if-else 语句，但这会重复我的代码...

I could use if-else statements but that will duplicate my code...

推荐答案

根据 API，您的示例中的块只会在记录不存在时执行.但是您不需要块，也不需要 if-else:

According to the API, the block in your example will only execute if the record does not exist. But you don't need a block, nor an if-else:

m = Model.where(parameters).first_or_create
m.some_method # executes regardless of whether record exists or not

请注意，对对象的某些验证可能已失败，因此 m 可能尚未持久化到数据库中.

Be aware that some validations on the object may have failed and therefore m may not have persisted to the database yet.

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