有更好的ruby方法吗-Isthereamorerubywayofdoingthis

3  

Indeed rescue is kind of a hack, id' probably split it up into two methods and then use try to fetch the name if available: http://api.rubyonrails.org/classes/Object.html#method-i-try

实际上，save是一种黑客，id'可能将它分为两种方法，然后使用try来获取名称(如果有的话):http://api.rubyonrails.org/classes/Object.html method-i-try

def current_company
  @current_company ||= Company.find_by_id(params[:company_id]) || @companies.try(:first) || current_user.try(:company)
end

def current_company_name
  current_company.try(:name)
end

2  

Company.find_by_id(params["company_id"]).name`

find and its derivates are meant to be used when you're sure-ish you'll have a positive result, and only in some cases (row was deleted, etc) errors. That's why it raises an exception. In your case, you're assuming it's gonna fail, so a regular where, which would return nil if no rows was found, would do better, and remove the first rescue

find和它的派生类应该在确定结果时使用，并且只有在某些情况下(删除行等)错误时才使用。这就是它引发一个例外的原因。在你的例子中，你假设它会失败，所以一个正则的where，如果没有找到行，它会返回nil，这样做会更好，并删除第一次救援

@companies.first.name rescue nil

could be replaced by

可以取代

@companies.first.try(:name)

I'll let you check the api for more on the topic of try. It's not regular ruby, it's a Rails addition.

我将让您检查api以获得更多关于try的主题。它不是普通的ruby，而是Rails的添加。

2  

Less "magic", simple code, simple to read:

少了“魔法”，代码简单，易读:

def current_company_title
 company = Company.where(id: params["company_id"]).presence
 company ||= @companies.try(:first)
 company ||= current_user.company
 company.name
end

Ps. Not a big fan of Rails' try method, but it solves the problem.

对Rails的尝试方法并不热衷，但它解决了问题。

1  

def current_company_title
    if params["company_id"]
        return Company.find_by_id(params["company_id"]).name
    elsif @companies
        return @companies.first.name
    else
        return current_user.company.name
    end
end

1  

The rescues are a hack, and will obscure other errors if they occur.

救援是一种手段，一旦发生其他错误，就会被掩盖。

Try this:

试试这个:

(Company.find_by_id(params["company_id"].name if Company.exists?(params["company_id"]) ||
(@companies.first.name if @companies && @companies.first) || 
current_user.company.name

then you can extract each of the bracketed conditions to their own methods to make it more readable, and easier to tweak the conditions:

然后，您可以将每个括号括起来的条件提取到它们自己的方法中，使其更具可读性，并且更容易调整条件:

company_name_from_id(params["company_id"]) || name_from_first_in_collection(@companies) || current_user_company_name

def company_name_from_id(company_id)
  company=Company.find_by_id(company_id)
  company.name if company
end

def name_from_first_in_collection(companies)
  companies.first.name if companies && companies.first
end

def current_user_company_name
  current_user.company.name if current_user.company
end

0  

[Company.find_by_id(params["company_id"]),
  @companies.to_a.first,
  current_user.company
].compact.first.name