Question

我的网页有两个下拉列表 1）包含书名 2）包含本书的链接。数据以XML文件的形式存储像这样的东西：

<?xml version="1.0" encoding="UTF-8"?>
<BookDetail>
<book>
    <bookName>Dollar Bahu</bookName>
    <link>http:\\DollarBahu.in</link>
</book>
<book>
    <bookName>The Lost Symbol</bookName>
    <link>http:\\TheLostSymbol.in</link>
</book>
<book>
    <bookName>Keep The Change</bookName>
    <link>http:\\KeepTheChange.in</link>
</book>
</BookDetail>

功能：在window.onload =函数（） { var xhttp = new XMLHttpRequest（）; xhttp.open（＆＃34; GET＆＃34;，＆＃34; bookDetails.xml＆＃34;，false）; xhttp.send（）; xhttp.onreadystatechange = function（） { if（xhttp.readyState == 4＆amp;＆amp; xhttp.status == 200） { var xml = xhttp.responseXML; var books = xml.getElementsByTagName（＆＃39; book＆＃39;）; var book = document.getElementById（＆＃39; book＆＃39;）， link = document.getElementById（＆＃39; link＆＃39;）;

                    for (i = 0; i < books.length; i++)
                    {
                        var obook = document.createElement('option'),
                        olink = document.createElement('option'),
                        tbook =   document.createTextNode(books[i].children[0].innerHTML),
                        tlink =   document.createTextNode(books[i].children[1].innerHTML);

                        obook.appendChild(tbook);
                        olink.appendChild(tlink);
                        book.appendChild(obook);
                        link.appendChild(olink);
                        map[tbook] = olink;
                    }
                    var updateLink = function(e)
                    {
                        //map[e.target.value].setAttribute('selected','');
                        //alert(map[e.target.value]);
                        for (var i = 0; i< link.children.length; i++)
                        {
                            link.children[i].removeAttribute('selected');
                        }
                           link.children[this.selectedIndex].setAttribute('selected','');
                    };
                    book.addEventListener('change', updateLink, false);
                }


                //var xmlString = "<BookDetail><book>    <bookName>Dollar Bahu</bookName>    <link>http:\\DollarBahu.in</link></book><book>    <bookName>The Lost Symbol</bookName>    <link>http:\\TheLostSymbol.in</link></book><book>    <bookName>Keep The Change</bookName>    <link>http:\\KeepTheChange.in</link></book></BookDetail>";
                //var xml = ( new window.DOMParser() ).parseFromString(xmlString, "text/xml"),i,
                //map = {};

            }

        }
    </script>

我已经在包含bookName的第一个下拉列表中连续插入了valus。现在我的问题是如何从XML中获取该特定bookName的第二个下拉列表中的book链接？

Answer 1

在bookName下拉列表的onchange事件中，您可以检索selectedIndex属性，然后使用该值获取相应的图书链接。

Answer 2

这是完整的解决方案：

  var xhttp = new XMLHttpRequest();
  xhttp.open("GET", "book.xml");
  xhttp.send();
  xhttp.onreadystatechange = function() {
      if (xhttp.readyState == 4 && xhttp.status == 200) {
        var books = xhttp.responseXML.getElementsByTagName('book');
        var book = document.getElementById('book'),
        link = document.getElementById('link');

        for (i = 0; i < books.length; i++) {
            var obook = document.createElement('option'),
                olink = document.createElement('option'),
                tbook = document.createTextNode(books[i].children[0].innerHTML),
                tlink = document.createTextNode(books[i].children[1].innerHTML);

            obook.appendChild(tbook);
            olink.appendChild(tlink);

            book.appendChild(obook);     
            link.appendChild(olink);      
    }
  }
}

var updateLink = function(e) {
    for (var i = 0; i< link.children.length; i++) {
        link.children[i].removeAttribute('selected');
    }
    link.children[this.selectedIndex].setAttribute('selected','');
};

book.addEventListener('change', updateLink, false);

使用此HTML：

<!doctype html>
<html>
<meta charset="utf-8" />
<head>
</head>
<body>
  <select name="book" id="book">
  </select>
  <select name="link" id="link">
  </select>
  <script type="text/javascript" src="main.js"></script>
</body>
</html>

这是book.xml

<?xml version="1.0" encoding="UTF-8"?>
<BookDetail>
<book>
    <bookName>Dollar Bahu</bookName>
    <link>http:\\DollarBahu.in</link>
</book>
<book>
    <bookName>The Lost Symbol</bookName>
    <link>http:\\TheLostSymbol.in</link>
</book>
<book>
    <bookName>Keep The Change</bookName>
    <link>http:\\KeepTheChange.in</link>
</book>
</BookDetail>

从另一个下拉列表中选择值时，在Deropdown中获取值

2 个答案: