结果使用ruby on rails多次重复该消息。

Question

我有这样的代码：

<% @lookup_coins.each do |x| %>
    <% if @symbol == '' %>
        <%= 'Sorry, but you forgot to write something, LOL'%>
    <% elsif @symbol == x %>
        <%= x["symbol"]%> <br/> <%= x["name"]%>: <%= number_to_currency(x['quote']['USD']['price'].round(2) , :unit => "$ ") %> <br/> <%= x["cmc_rank"]%> <br/> 
    <% else 'Sorry, there was a mistake, try again'%>
<% end %>

信息看起来像这样：

[{"id"=>1, "name"=>"Bitcoin", "symbol"=>"BTC", "slug"=>"bitcoin", "num_market_pairs"=>9713, "date_added"=>"2013-04-28T00:00:00.000Z", "tags"=>["mineable", "pow", "sha-256", "store-of-value", "state-channels", "coinbase-ventures-portfolio", "three-arrows-capital-portfolio", "polychain-capital-portfolio"], "max_supply"=>21000000, "circulating_supply"=>18633612, "total_supply"=>18633612, "platform"=>nil, "cmc_rank"=>1, "last_updated"=>"2021-02-20T07:45:02.000Z", "quote"=>{"USD"=>{"price"=>55541.51774356704, ...

我不知道怎样做才是正确的。

Answer 1

看起来您无法与实际的哈希值匹配，而是期望@symbol与symbol完全匹配，而实际情况并非如此。

其次，您还在每次通过循环打印“忘记写东西”消息，这是错误的。您可以摆脱循环，只需使用find立即定位条目，然后作为额外的好处，您可以更容易地检测到“未命中”条件。

只需查看是否能找到匹配的条目，否则将显示消息。

修复方法看起来像这样：

<%- if @symbol.blank? -%>
  Sorry, but you forgot to write something.
<%- else -%>
  <%- found = @lookup_coins.find { |c| c['symbol'] == @symbol } -%>
  <%- if (found) -%>
    <%= found["symbol"]%> <br/> <%= found["name"]%>:
    <%= number_to_currency(found['quote']['USD']['price'].round(2), :unit => "$ ") %>
    <br/>
     <%= found["cmc_rank"]%> <br/> 
  <%- else -%>
    Sorry, there was a mistake, try again
  <%- end -%>
<%- end -%>

这里使用比== ''更宽松的@symbol.blank?，因为它也会拒绝一堆空格和/或制表符。

提示:不要使用<%= '...' %>，只需按原样放置文本即可。默认设置是回显。

Answer 2

<% if @symbol %>
<%@resultant_symbol = @lookup_coins['data'].select {|lookup_coin| lookup_coin["symbol"] == @symbol }%>
<%if @resultant_symbol.present?%>
   <% x = @resultant_symbol.first %>
   <%= x["symbol"]%> <br/> <%= x["name"]%>: <%= number_to_currency(x['quote']['USD']['price'].round(2) , :unit => "$ ") %> <br/> <%= x["cmc_rank"]%> <br/> 
<%else%>
   <%= @symbol = 'Sorry, there was a mistake, try again'%>
<%end%>