Rails：如何让Jquery在单击后更新数据库列 [英] Rails: How to get Jquery to update a database column after a click

问题描述

首先，我知道我想要做的事情并不是典型的Rails。我愿意接受更好的替代方案。我是rails的新手，欢迎提出建议：）

To start out, I know what I am trying to do is not typical to Rails. I open to suggestions to better alternatives. I am novice with rails so suggestions are welcome :)

基本上，我有一个有5个通知的通知栏。在用户单击并看到通知后，我想将数据库中的a列设置为true。

Basically, I have a notifications bar that has 5 notifications. After a user clicks and sees the notifications I want to set the a column in the database called seen to true.

这是我的Jquery函数：

Here is my Jquery function:

<script type="text/javascript">
            $(document).ready(function(){
              $("button").click(function(){
                    $("div#count").html("<%= escape_javascript(render('shared/notification_count')) %>");
              });
            });
</script>

这是我试图仅在点击后执行的代码（位于_notification_count.html中。 erb）

And here is the code I am trying to execute only after the click(located in _notification_count.html.erb)

<% notification_ids =   current_user.notifications.map(&:id).join(', ')%>
<% sql = "UPDATE notifications SET SEEN = true where id IN(#{notification_ids})" %>
<% User.connection.select_all(sql) %>

然而，看起来这个代码在页面加载时自动执行，而不是在点击之后执行。我的问题是什么？

However, it appears that this code is getting executed automatically when the page loads and not after the click. What is my problem?

推荐答案

首先，你不能简单地附上 render 按钮对数据库进行更改（无论是读取还是写入）。您必须使用类似

Firstly, you cannot simply attach a render to your button to make changes to your database (whether it's a read or a write). You must make an AJAX call back to your controller using something like

$.ajax({
    url: "/path/to/your/method",
    type: "GET",
    dataType: "script"
});

在您的控制器中，您将处理您需要做的事情，然后使用a渲染您的js文件

And in your controller you will handle what you need to do, and then render your js file with a

respond_to do |format|
    format.js {render 'shared/notification_count'}
end

this是因为当用户点击你的按钮时，代码将在客户端执行，但如果你从未向服务器发回请求，那么你将无法看到数据库的更新版本。我建议你在这个上阅读更多内容，这对我帮助很大。

This is because when a user clicks on your button, the code will be executed on the clients side, but if you never make a request back to the server, then you will not be able to see the updated version of your database. I suggest you reading more on this, that helped me a lot.

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