Question

我有一个rails 4 app。在控制器中，我遍历数据库中的每个赋值条目，以检查需求是否与多个赋值相关联。但是，我无法弄清楚如何向控制器添加计数器，即hit = 0，hit = 1等。

编辑：分配和要求之间的关系是HABTM。

我的代码如下：

def check_requirements
 @assignments = Assignment.all
 @assignment = Assignment.find(params[:id])
 @requirement = Requirement.find(params[:requirement_id])
 @assignments.each do |assignment|
      if assignment.include(requirement)
        #here's where the counter should go
      end
  end
  if counter is greater than zero or one, do nothing
  else @assignment.delete(requirement)
end

Answer 1

您可以使用Enumerable#each_with_index

def check_requirements
 @assignments = Assignment.all
 @assignment = Assignment.find(params[:id])
 @requirement = Requirement.find(params[:requirement_id])
 @assignments.each_with_index do |assignment,hit|
      if assignment.include(requirement)
        p "hit : #{hit}"
      end
  end
  if counter is greater than zero or one, do nothing
  else @assignment.delete(requirement)
end

Answer 2

def check_requirements
 @assignments = Assignment.all
 @assignment = Assignment.find(params[:id])
 @requirement = Requirement.find(params[:requirement_id])
 counter = 0
 @assignments.each do |assignment|
      if assignment.include(requirement)
        counter+=1
      end
  end
  if counter is greater than zero or one, do nothing
  else @assignment.delete(requirement)
end

向控制器添加计数器。 Rails 4

2 个答案: