下面我们看一下，如何用javascript脚本调用Yahoo! Search API实现搜索的效果，全部脚本如下：
  

/*
 * yahoo_search_api.js
 * Part of the Yahoo! Search Sidebar for Firefox
 * powered by Yahoo! Search web services (http://api.search.yahoo.com)
 * Written by Marc Abramowitz (http://marc.abramowitz.info)
 * Copyright (C) 2005 Yahoo! Inc.
 * www.knowsky.com
 */

function Yahoo_Search() {}

Yahoo_Search.baseURL = function () {
  return "http://api.search.yahoo.com/WebSearchService/V1/";
}

Yahoo_Search.appid = function () {
  return "YahooSearchSidebar";
}

Yahoo_Search.baseArgs = function () {
  return "appid=" + this.appid();
}

Yahoo_Search.Results = function (args) {
  var xmlUrl = this.baseURL() + "webSearch?"
       + this.baseArgs()
       + "&query=" + args["Doc"]
       + "&zip="
       + "&start=" + args["First"]
       + "&results=" + args["Count"];
  var xmlhttp = new XMLHttpRequest();
  xmlhttp.open("GET", xmlUrl, false);
  xmlhttp.send(null);
  return this.readXML(xmlhttp.responseXML);
}

Yahoo_Search.readXML = function (xmlDoc) {
  try {
    var retVal = new Array();
    var resultSet = xmlDoc.getElementsByTagName("ResultSet")[0];
    var totalResultsAvailable = parseInt(resultSet.getAttribute("totalResultsAvailable")); 
    var totalResultsReturned = parseInt(resultSet.getAttribute("totalResultsReturned"));
    var firstResultPosition = parseInt(resultSet.getAttribute("firstResultPosition"));
    var start = firstResultPosition;
    var end = firstResultPosition + totalResultsReturned - 1; 
    var results = xmlDoc.getElementsByTagName("Result");
    for (var i = 0; i < results.length; i++) {
      var result = results;         
      var title = result.getElementsByTagName('Title')[0].firstChild.nodeValue;
      var summary = '';
      if (result.getElementsByTagName('Summary')[0].firstChild) {
        summary = result.getElementsByTagName('Summary')[0].firstChild.nodeValue;
      }
      var clickUrl = result.getElementsByTagName('ClickUrl')[0].firstChild.nodeValue;
      var url = result.getElementsByTagName('Url')[0].firstChild.nodeValue;
      retVal = { I: start + i, Title: title, Summary: summary, ClickUrl: clickUrl, Url: url };
    }

    return retVal;
  } catch(exception) {
    alert('Exception occurred while reading XML (i=' + i + '; start=' + start + ';end=' + end + '): ' + exception);
  }
}