从雅虎

Question

选择的实时汇率为一种货币对我使用这个API链接：

http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20%28%22USDEUR%22,%20%22USDJPY%22,%20%22USDBGN%22,%20%22USDCZK%22,%20%22USDDKK%22,%20%22USDGBP%22,%20%22USDHUF%22,%20%22USDLTL%22,%20%22USDLVL%22,%20%22USDPLN%22,%20%22USDRON%22,%20%22USDSEK%22,%20%22USDCHF%22,%20%22USDNOK%22,%20%22USDHRK%22,%20%22USDRUB%22,%20%22USDTRY%22,%20%22USDAUD%22,%20%22USDBRL%22,%20%22USDCAD%22,%20%22USDCNY%22,%20%22USDHKD%22,%20%22USDIDR%22,%20%22USDILS%22,%20%22USDINR%22,%20%22USDKRW%22,%20%22USDMXN%22,%20%22USDMYR%22,%20%22USDNZD%22,%20%22USDPHP%22,%20%22USDSGD%22,%20%22USDTHB%22,%20%22USDZAR%22,%20%22USDISK%22%29&env=store://datatables.org/alltableswithkeys

但似乎这不是选择与特定ID的元素的方式。

因此，检查该链接，我的问题是，里面的结果 - >率元素与不同的ID，因此现在我只希望USDEUR指数，我想类似的东西

<script> 
      setInterval(function(){ 
       //somehow convert xml to json 
       $.getJSON('http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20%28%22USDEUR%22,%20%22USDJPY%22,%20%22USDBGN%22,%20%22USDCZK%22,%20%22USDDKK%22,%20%22USDGBP%22,%20%22USDHUF%22,%20%22USDLTL%22,%20%22USDLVL%22,%20%22USDPLN%22,%20%22USDRON%22,%20%22USDSEK%22,%20%22USDCHF%22,%20%22USDNOK%22,%20%22USDHRK%22,%20%22USDRUB%22,%20%22USDTRY%22,%20%22USDAUD%22,%20%22USDBRL%22,%20%22USDCAD%22,%20%22USDCNY%22,%20%22USDHKD%22,%20%22USDIDR%22,%20%22USDILS%22,%20%22USDINR%22,%20%22USDKRW%22,%20%22USDMXN%22,%20%22USDMYR%22,%20%22USDNZD%22,%20%22USDPHP%22,%20%22USDSGD%22,%20%22USDTHB%22,%20%22USDZAR%22,%20%22USDISK%22%29&env=store://datatables.org/alltableswithkeys', function(data) { 
       var USD = 1/data.query.results.rate['USDEUR'].Rate * 1.955 
       document.getElementById('output-value').innerHTML = USD * document.getElementById('input-value').value;  
       }); 
      }, 500); 
     </script> 

Answer 1

这很容易理解，如果你通过一个解码器运行URL（例如，PHP的urldecode()函数，这是我做的，或者是在线提供的众多解码器之一）。 URL只是这个的一个编码版本：

http://query.yahooapis.com/v1/public/yql?q= 
select * 
from yahoo.finance.xchange 
where pair in ("USDEUR", "USDJPY", "USDBGN", "USDCZK", "USDDKK", 
    "USDGBP", "USDHUF", "USDLTL", "USDLVL", "USDPLN", "USDRON", 
    "USDSEK", "USDCHF", "USDNOK", "USDHRK", "USDRUB", "USDTRY", 
    "USDAUD", "USDBRL", "USDCAD", "USDCNY", "USDHKD", "USDIDR", 
    "USDILS", "USDINR", "USDKRW", "USDMXN", "USDMYR", "USDNZD", 
    "USDPHP", "USDSGD", "USDTHB", "USDZAR", "USDISK") 
&env=store://datatables.org/alltableswithkeys 

我添加了一点格式，以使它明显是怎么回事。这是一个YQL (Yahoo! Query Language)语句（实际上只是一个SQL SELECT语句）和一个配对名称列表。

为了得到你想要的结果，刚刚从URL删除其他对，就像这样：

http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20%28%22USDEUR%22%29&env=store://datatables.org/alltableswithkeys

响应（格式化的可读性）：

<?xml version="1.0" encoding="UTF-8"?> 
<query xmlns:yahoo="http://www.yahooapis.com/v1/base.rng" yahoo:count="1" yahoo:created="2016-01-26T19:43:48Z" yahoo:lang="en-US"> 
    <results> 
     <rate id="USDEUR"> 
      <Name>USD/EUR</Name> 
      <Rate>0.9217</Rate> 
      <Date>1/26/2016</Date> 
      <Time>7:43pm</Time> 
      <Ask>0.9218</Ask> 
      <Bid>0.9217</Bid> 
     </rate> 
    </results> 
</query> 
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