The DOM (Document Object Model) defines a standard way for accessing and manipulating documents. The XML DOM The XML DOM (XML Document O...
The DOM (Document Object Model) defines a standard way for accessing and manipulating documents.
The XML DOM
The XML DOM (XML Document Object Model) defines a standard way for accessing and manipulating XML documents.The DOM views XML documents as a tree-structure. All elements can be accessed through the DOM tree. Their content (text and attributes) can be modified or deleted, and new elements can be created. The elements, their text, and their attributes are all known as nodes.
In the examples below we use the following DOM reference to get the text from the <to> element:
xmlDoc.getElementsByTagName("to")[0].childNodes[0].nodeValue
- xmlDoc - the XML document created by the parser.
- getElementsByTagName("to")[0] - the first <to> element
- childNodes[0] - the first child of the <to> element (the text node)
- nodeValue - the value of the node (the text itself)
The HTML DOM
The HTML DOM (HTML Document Object Model) defines a standard way for accessing and manipulating HTML documents.All HTML elements can be accessed through the HTML DOM.
In the examples below we use the following DOM reference to change the text of the HTML element where id="to":
document.getElementById("to").innerHTML=
- document - the HTML document
- getElementById("to") - the HTML element where id="to"
- innerHTML - the inner text of the HTML element
Parsing an XML File - A Cross browser Example
The following code loads an XML document ("note.xml") into the XML parser:<html>
<head>
<script type="text/javascript">
function parseXML()
{
try //Internet Explorer
{
xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
}
catch(e)
{
try //Firefox, Mozilla, Opera, etc.
{
xmlDoc=document.implementation.createDocument("","",null);
}
catch(e)
{
alert(e.message);
return;
}
}
xmlDoc.async=false;
xmlDoc.load("note.xml");
document.getElementById("to").innerHTML=
xmlDoc.getElementsByTagName("to")[0].childNodes[0].nodeValue;
document.getElementById("from").innerHTML=
xmlDoc.getElementsByTagName("from")[0].childNodes[0].nodeValue;
document.getElementById("message").innerHTML=
xmlDoc.getElementsByTagName("body")[0].childNodes[0].nodeValue;
}
</script>
</head>
<body onload="parseXML()">
<h1>1000sourcecodes Internal Note</h1>
<p><b>To:</b> <span id="to"></span><br />
<b>From:</b> <span id="from"></span><br />
<b>Message:</b> <span id="message"></span>
</p>
</body>
</html> |
Important Note
To extract the text "Jani" from the XML, the syntax is:getElementsByTagName ("from")[0].childNodes[0].nodeValue |
In the XML example there is only one <from> tag, but you still have to specify the array index [0], because the XML parser method getElementsByTagName() returns an array of all <from> nodes.
Parsing an XML String - A Cross browser Example
The following code loads and parses an XML string:<html>
<head>
<script type="text/javascript">
function parseXML()
{
text="<note>";
text=text+"<to>Tove</to>";
text=text+"<from>Jani</from>";
text=text+"<heading>Reminder</heading>";
text=text+"<body>Don't forget me this weekend!</body>";
text=text+"</note>";
try //Internet Explorer
{
xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
xmlDoc.async="false";
xmlDoc.loadXML(text);
}
catch(e)
{
try // Firefox, Mozilla, Opera, etc.
{
parser=new DOMParser();
xmlDoc=parser.parseFromString(text,"text/xml");
}
catch(e)
{
alert(e.message);
return;
}
}
document.getElementById("to").innerHTML=
xmlDoc.getElementsByTagName("to")[0].childNodes[0].nodeValue;
document.getElementById("from").innerHTML=
xmlDoc.getElementsByTagName("from")[0].childNodes[0].nodeValue;
document.getElementById("message").innerHTML=
xmlDoc.getElementsByTagName("body")[0].childNodes[0].nodeValue;
}
</script>
</head>
<body onload="parseXML()">
<h1>1000sourcecodes Internal Note</h1>
<p><b>To:</b> <span id="to"></span><br />
<b>From:</b> <span id="from"></span><br />
<b>Message:</b> <span id="message"></span>
</p>
</body>
</html>
|
Note: Internet Explorer uses the loadXML() method to parse an XML string, while other browsers uses the DOMParser object.
