如何替换字符串中的模式 [英] How to replace a pattern in a string

问题描述

我构建了一个页面，该页面根据 params 的呈现方式有所不同。逻辑是这样的：

I built a page that is rendered differently depending on params. The logic is something like this:

<% if params[:x] == "1" %>
  <!--render version A-->
<% elsif params[:x] == "2" %>
  <!--render version B-->
<% elsif params[:x] == "3" %>
  <!--render version C-->
<% end %>

我希望每个版本都有两个链接，链接到其他两个版本，因此网址应具有不同的参数。我有一个URL字符串 original_url ，它是：

I want each version to have two links which link to the other two versions, so the urls should have different params. I have a url string original_url, which is:

"localhost:3000/page?x=1"

，并希望根据参数。其他两个版本应该是：

and want to replace its parameter depending on params. The other two versions should be:

"localhost:3000/page?x=2"
"localhost:3000/page?x=3"

如何消除模式？x = [number] from original_url 并替换为其他内容？

How can I eliminate the pattern ?x=[number] from original_url and replace it with something else?

对于版本1，我可以这样做

For version 1, I could do

request.original_url.sub("?x=1", "?x=2")

然后

request.original_url.sub("?x=1", "?x=3")

但是在其他两个版本上将无法使用。

but then that wouldn't work on the other two versions.

推荐答案

我会针对链接执行此操作

I would do this for the links

<%= ([1,2,3]- [params[:x]]).each do |link_number| %>
   <%= link_to "Version #{link_number}", "/page?x=#{link_number}" %>
<% end %>

这样，每次加载页面时，都会存在指向其他2个版本的链接。

This way everytime the page is loaded the link to the other 2 versions will exist.

您可以通过控制器处理部分零件（似乎更好），也可以使用类似的东西：

You could handle the partials through the controller (which seems better) or use something like:

<%= render "version_#{['A','B','C'][params[:x] - 1]}" %>

在没有更好地理解问题的情况下，我无能为力。

Without a better understanding of the problem I cannot assist beyond this point.

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