Rails中的fields_for方法用于在表单中嵌套显示关联模型的属性。它允许我们在表单中编辑关联模型的属性,并将这些属性与主模型关联起来。 当使用fields_for方法时,如果关联模型的属性为空或未定义,它将返回nil。这通常发生在关联模型尚未创建或没有相关数据时。 在这种情况下,我们可以使用build_association方法来创建关联模...
在Rails 5中,使用fields_for方法可以在ActiveModel表单中处理嵌套的关联模型。它允许我们在表单中创建、编辑和删除关联模型的记录。 fields_for方法的语法如下: 代码语言:ruby 复制 <%=form.fields_for:association_name,@associated_modeldo|association_form|%> <!-- 表单字段 --><%end%> ...
这里我们使用fields_for来为@project的每个task构建一个伪表单,实际上还是@project最外层同一个表单,不过这样我们就 可以在同一表单里添加额外的Model对象字段,再看一个官方的例子: <% form_for :person,@person, :url => { :action =>"update"}do|person_form| %> First name: <%= person_form.text_fie...
But the thing is, this only shows me the fields if the user already has a job to his profile, and I am able to update that. But in this case the array is empty and there will be no iteration. What could I use instead of this, to be sure the forms appear even if the user has...
如何修复fields_for错误:@“不允许作为实例变量n”在Rails? - 我的目标是使用户能够从父博客表单提交多个NewsImages。 我的博客模型如下所示: # == Schema Information # Schema version: 20091006171847 # # Table name: blogs #...
Here is the part of the form with the fields for request_files: Upload Files: <%= f.fields_for :request_files do |p| %> <%= p.file_field :file, :multiple => true, name: "request_files[file][]" %> <% end %> <% if params[:controller] ==...
感觉你错过了这里的副本?
the form_for helper on line 1 sets up a standard HTML form. But it does more. The first parameter, : order,tells the method that it’s dealing with an object in an instance variable named @order. The helper uses this information when naming fields and when arranging for the field value...
Steps to reproduce Model with several has_many relation has a form_for with nested fields_for, some of them are specified with a collection of children. More details described on SO question Expected behavior Upon failed validation, form...
我们用rails中得 accepts_nested_attributes_for实现这个功能。 新建和修改页面调用模板页面_form.html.erb #form页面主要实现代码 <%= f.fields_for:strip_rulesdo|strip_rule| %> <%= render"strip_rule",:f=> strip_rule %> <%end%> <%= raw link_to_add_fields("增加一条新规则", f,:strip_...