ruby on rails 入门注意事项 2

参考前一篇博客:

 http://hw1287789687.iteye.com/blog/2288230

(7)更新记录(保存更新)

我的写法:

 

def update

    articles = Article.update(params[:id], params.require(:article).permit(:title, :text))
    redirect_to :action => 'list'
  end

  最佳实践:

 

 

def update
    @article = Article.find(params[:id])
    @article.update(params.require(:article).permit(:title, :text))

    redirect_to :action => 'list'
  end

 先通过id查询记录,然后再更新,而不是直接更新

 

(8)手动指定视图

 

render template: "articles/show"

  类似于springMVC中的:

 等价于:

render :show

下面的方式达到的效果是完全相同的: 

render :edit
render action: :edit
render "edit"
render "edit.html.erb"
render action: "edit"
render action: "edit.html.erb"
render "books/edit"
render "books/edit.html.erb"
render template: "books/edit"
render template: "books/edit.html.erb"
render "/path/to/rails/app/views/books/edit"
render "/path/to/rails/app/views/books/edit.html.erb"
render file: "/path/to/rails/app/views/books/edit"
render file: "/path/to/rails/app/views/books/edit.html.erb"

 

 

 

 

(9)浏览器跳转

使用redirect_to

 

# 增加,持久化到数据库
  def create
    articles = Article.create(params.require(:article).permit(:title, :text))
    # render plain: params[:article].inspect
    redirect_to :action => 'list'
  end

 类似于spring MVC中的

response.sendRedirect

 

 

 

(10)CRUD

增:

Article.create(params.require(:article).permit(:title, :text))

 

删除:

id=params[:id]
    Article.find(id).destroy;

 

改:

@book = Book.find(params[:id])
@book.update(book_params)

 

查

条件查询

@article=Article.find_by(id: id)

 

查询所有

@articles=Article.all

 

(11)指定请求方式

使用method

<%= form_for :article, method: "PUT", url: {action: "update"} do |f| %>

 (12)rubyonrails中好像没有Java Web中的forward跳转

知道在rails中forward跳转的同学麻烦告诉我下

(13)构造表单时推荐使用form_for

we used form_for tag for the form action. It will perform better than form_tag. Why because it will create interaction with the Model easily. Therefore it is better to use form_for tag whenever you need interaction between the model and the form fields.

翻译:

我们使用form_for实现表单提交.它比form_tag 更强大.为什么呢?

因为form_for 可以更方便地与Modeal进行交互(数据绑定).

因此,无论什么时候,你需要在model和表单之间进行数据传递时推荐使用form_for.

 参考:

http://www.tutorialspoint.com/ruby-on-rails/rails-controllers.htm

http://guides.rubyonrails.org/layouts_and_rendering.html

http://www.tutorialspoint.com/ruby-on-rails/rails-views.htm

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