js如何访问xml

<script type="text/javascript">

x=xmlDoc.getElementsByTagName("title")[0];
y=x.childNodes[0];
txt=y.nodeValue;

//结果：txt = "Everyday Italian"


//获取属性值 - getAttribute()

xmlDoc=loadXMLDoc("books.xml");
txt=xmlDoc.getElementsByTagName("title")[0].getAttribute("lang");

//结果：txt = "en"


//获取属性值 - getAttributeNode()

x=xmlDoc.getElementsByTagName("title")[0].getAttributeNode("lang");
txt=x.nodeValue;


//改变文本节点得值

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc .getElementsByTagName("title")[0].childNodes[0];
x.nodeValue="Easy Cooking";


//改变属性的值

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc .getElementsByTagName("book");
x[0].setAttribute("category","food");


//删除元素节点

xmlDoc = loadXMLDoc("books.xml");
y = xmlDoc.getElementsByTagName("books")[0];
xmlDoc.documentElement.removeChild(y);


//删除自身

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("book")[0];
x.parentNode.removeChild(x);


//删除文本节点

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("title")[0];
y = x.childNodes[0];
x.removeChild(y);


//清空文本节点

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("title")[0];
x.nodeValue = ""；


//根据名称删除属性节点

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("book");
x[0].removeAttribute('category');


//根据对象删除属性节点

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("book");
for(var i=0;i<x.length;i++)...{
       while(x[i].attributes.length>0)...{
                attnode=x[i].attributes[0];
                old_att=x[i].removeAttributeNode(attnode);
       }
}
x[0].removeAttribute(category);

</script>

		

//replaceChild() 方法用于替换节点。
xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.documentElement;

//create a book element, title element and a text node
newNode = xmlDoc.createElement("book");
newTitle = xmlDoc.createElement("title");
newText = xmlDoc.createTextNode("A Notebook");

//add the text node to the title node,
newTitle.appendChild(newText);
//add the title node to the book node
newNode.appendChild(newTitle);

y = xmlDoc.getElementsByTagName("book")[0];
//replace the first book node with the new node
x.replaceChild(newNode,y);


//替换文本节点中的数据

replaceData()方法用于替换文本节点中的数据。
replaceData()方法有三个参数：
offset-在何处开始替换字符。Offset值以0开始。
length-要替换多少字符。
string-要插入的字符串。

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("title")[0].childNodes[0];
x.replaceDate(0,8,"Easy");

用nodeValue属性来替换文本节点中的数据。
xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("title")[0].childNodes[0];
x.nodeValue="Easy Italian";


//创建新的元素节点

createElement()方法创建新的元素节点。
xmlDoc = loadXMLDoc("books.xml");
newNode = xmlDoc.createElement("edition");
x = xmlDoc.getElementsByTagName("book")[0];
x.appendChild(newNode);


//创建新的属性节点

xmlDoc = loadXMLDoc("books.xml");
newAtt = xmlDoc.createAttribute("edition");
newAtt.nodeValue ="first";
x = xmlDoc.getElementsByTagName("title");
x[0].setAttributeNode(newAtt);


//通过setAttribute创建属性。

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("book");
x[0].setAttribute("edition","first");


//创建文本节点

createTextNode()方法创建新的文本节点。
xmlDoc = loadXMLDoc("books.xml");
newNode = xmlDoc.createElement("publisher");
newText = xmlDoc.createTextNode("english");
newNode.appendChild(newText);
x = xmlDoc.getElementsByTagName("book")[0];
x.appendChild(newNode);


//创建一个CDATA Section节点

xmlDoc = loadXMLDoc("books.xml");
newCDATA = xmlDoc.createCDATASection("Special offer & Book Sale");
x = xmlDoc.getElementsByTagName("book")[0];
x.appendChild(newCDATA);


//创建注释节点

xmlDoc = loadXMLDoc("books.xml");
newComment = xmlDoc.createComment("Revised March 2008");
x=xmlDoc.getElementsByTagName("book")[0];
x.appendChild(newComment);


//添加节点

xmlDoc = loadXMLDoc("books.xml");
newNode = xmlDoc.createElement("publisher");
x = xmlDoc.getElementsByTagName("book")[0];
x.appendChild(newNode);


//插入节点--insertBefore()

xmlDoc = loadXMLDoc("books.xml");
newNode = xmlDoc.createElement("book");
x = xmlDoc.documentElement;
y = xmlDoc.getElementsByTagName("book")[3];
x.insertBefore(newNode,y);


//添加新属性

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("book");
x[0].setAttribute("edition","first");


//向文本节点添加文本--insertData()

xmlDoc = loadXMLDoc("books.xml");
x = xmlDoc.getElementsByTagName("title")[0].childNodes[0];
x.insertData(0,"Easy");


//复制节点

xmlDoc = loadXMLDoc("books.xml");
oldNode = xmlDoc.getElementsByTagName("book")[0];
newNOde = oldNode.cloneNode(true);
xmlDoc.documentElement.appendChild(newNode);
//output all titles
y = xmlDoc.getElementsByTagName("title");
for(var i=0;i<y.length;i++)...{
     document.write(y[i].childNodes[0].nodeValue);
     document.write("<br/>");
}