如何在以下情况下调用ruby方法：触发onchange事件（ruby on rails 4）？

I am pretty new to ruby on rails... On my _form.html.erb I have a collection_select field, which is populated from a Model called Product. The Product's table columns are id, name, and price. Once I select an item (product) from the collection I would like to populate a text field with the price of the selected product.

我对rails上的ruby很新...在我的_form.html.erb上我有一个collection_select字段,它是从名为Product的Model中填充的。产品的表格列是ID,名称和价格。一旦我从集合中选择了一个项目(产品),我想用所选产品的价格填充一个文本字段。

So far I have the following code IOT trigger an event when selecting an item:

到目前为止,我有以下代码IOT在选择项目时触发事件:

<%= collection_select( :warehouse, :product_id, Product.all, :id, :name, {}, {:onchange => "alert('Hello World');"} )%>

How can I call a ruby method which would let me populate the text_field with the corresponding price for the selected product?

如何调用ruby方法,让我使用所选产品的相应价格填充text_field?

For the method I was thinking something like...

对于这种方法,我想的是......

def set_price
      @price = Product.find(params[:id]).price
end

1 个解决方案

#1

The erb snippet

erb片段

<%= collection_select( :warehouse, :product_id, Product.all, :id, :name, {}, {:onchange => "alert('Hello World');"} )%>

generates the html snippet like this

像这样生成html代码段

<select name="warehouse[product_id]" onchange="alert('Hello World');">
  <option value="1">Product 1</option>
  <option value="2">Product 2</option>
  ...
</select>

So the content of onchange is just a piece of javascript, which runs on browsers. There is no way to let onchange run ruby code directly. All you can do is send an AJAX request in onchange, and let your Rails application respond to that request.

所以onchange的内容只是一段javascript,可以在浏览器上运行。没有办法让onchange直接运行ruby代码。您所能做的就是在onchange中发送一个AJAX请求,让您的Rails应用程序响应该请求。

#1