我试图使用相同的表单来创建一个新的数据库条目,显示当前的DB信息,现在更新DB信息,但仍然试图在控制器内的create方法中进行修补。我试过使用first_or_initialize和find_or_initialize_by_name,但似乎无法让他们在这种情况下工作。我正在考虑尝试一种if something.nil? / of类型的设计。我是新来的,任何帮助都是非常...
find_or_initialize 是Ruby on Rails 框架中的一个方法,用于查找一个记录,如果找不到,则初始化一个新的对象。这个方法在处理表单提交时特别有用,因为它可以避免创建重复的记录。 相关优势 防止重复记录:通过 find_or_initialize,可以确保不会因为重复提交表单而创建重复的记录。 提高性能:相比于先查找再创建的逻辑...
def initialize(first, initials, last) @first = first @initials = initials @last = last end 也可以手动指定所需的列名与字段的映射 composed_of :name,:class_name => "Name" , :mapping =>[ # database ruby %w[ first_name first ], #列名,属性名 %w[ initials initials ], %w[ last_name...
scoped_by_... 改为: where(...). find_or_initialize_by_... 改为:where(...).first_or_initialize. find_or_create_by_... 改为:find_or_create_by(...) 或者 where(...).first_or_create. find_or_create_by_...! 改为 find_or_create_by!(…)或者 where(...).first_or_create!
The initialize method of Rack::Builder will take the block here and execute it within an instance of Rack::Builder. This is where the majority of the initialization process of Rails happens. The require line for config/environment.rb in config.ru is the first to run:...
# If you pass a Symbol as the first argument, then a corresponding cache # store class under the ActiveSupport::Cache namespace will be created. # For example: # # ActiveSupport::Cache.lookup_store(:memory_store) initialize_framework_caches ...
First, try this link to see if there are any existing issue reports for this error: https://github.com/rubygems/rubygems/search?q=No+such+file+or+directory+-+%2Fhome%2Fuser%2F.rvm%2Fgems%2Fjruby-9.4.10.0%2Fgems%2Fpsych-5.2.3-java%2Fdeps.lst&type=Issues If there aren't any ...
FIND_OR_INITIALIZE_BY方法的工作方式与FIND_OR_CREATE_BY相同，但它将调用new而不是create。这意味着...
1. Create a Rails project First, let's set up your local development environment and initialize a new Rails project. Install Rails If you haven't yet, complete the steps in the officialRails installation guideto install both Ruby and Rails on your development machine. ...
first :foreign_key :id primary_key :include :joins :limit :method :order :params :popup :remote :select :shallow_routes :string :through :through_conditions :update absolutepath abstract_class abstract_renderer abstract_store.rb abstract_storerb abstractrequest accept accepts_nested_attributes_ has...