rails可以重構這個模型代碼嗎？

Question

我想更好地結合發現者。

if params[:sort] 
    if params[:sort] == 'industry_id' 
    if params[:industry_id] 
     @companies = Company.find_all_by_industry_id(params[:industry_id], :joins => "left join industries ind on industry_id = ind.id", :order => "ind.name" + " " + sort_direction) 
    else 
     @companies = Company.all(:joins => "left join industries ind on industry_id = ind.id", :order => "ind.name" + " " + sort_direction) 
    end 
    else 
    if params[:industry_id] 
     @companies = Company.find_all_by_industry_id(params[:industry_id], :order => sort_column + " " + sort_direction) 
    else 
     @companies = Company.all(:order => sort_column + " " + sort_direction) 
    end 
    end 
else 
    if params[:industry_id] 
    @companies = Company.find_all_by_industry_id(:joins => "left join industries ind on industry_id = ind.id", :order => "ind.name" + " " + sort_direction) 
    else 
    @companies = Company.all 
    end 
end 

Answer 1

假設你有以下型號：

class Company 
    belongs_to :industry 

    def self.search p 
    opt = {:conditions => {}} 
    opt[:order] = (p[:sort] == "industry_id") ? "industries.name" : p[:sort] 
    opt[:order]+= " " + (p[:sort_direction] || "ASC") if opt[:order].present? 
    opt[:conditions][:industry_id] = p[:industry_id] if p[:industry_id].present? 
    if (p[:sort] == 'industry_id') or p[:industry_id].present? 
     opt[:include] = :industry 
    end 
    all(opt) 
    end 
end 

class Industry 
    has_many :companies 
end 

現在你可以在你的控制器使用方法search：

Company.search(params) 

Answer 2

我是否錯過了一些東西，或者是否全部歸結爲此？

sort_joins = { 'ind.name' => 'left join industries ind on industry_id = ind.id' } 
if params[:sort] == 'industry_id' || !params[:sort] 
    sort_column = 'ind.name' 
end 

sort_column = nil if sort_column && !params[:industry_id] 

options = { } 
if sort_column 
    options[:sort] = "#{sort_column} #{sort_direction}" 
    options[:joins] = sort_joins[sort_column] if sort_joins[sort_column] 
end 
if params[:industry_id] 
    @companies = Company.find_all_by_industry_id(params[:industry_id], options) 
else 
    @companies = Company.all(options) 
end