XML Applications
This chapter demonstrates some HTML applications using XML, HTTP, DOM, and JavaScript.
The XML Document Used
In this chapter we will use the XML file called "cd_catalog.xml".Display XML Data in an HTML Table
This example loops through each <CD> element, and displays the values of the <ARTIST> and the <TITLE> elements in an HTML table:Example
<html>
<head>
<style>
table, th, td {
border: 1px solid black;
border-collapse:collapse;}
th, td {
padding: 5px;}</style>
</head>
<body>
<table id="demo"></table>
<script>
function loadXMLDoc() {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
myFunction(this);
}
};
xmlhttp.open("GET", "cd_catalog.xml", true);
xmlhttp.send();
}
function myFunction(xml) {
var i;
var xmlDoc = xml.responseXML;
var table="<tr><th>Artist</th><th>Title</th></tr>";
var x = xmlDoc.getElementsByTagName("CD");
for (i = 0; i <x.length; i++) {
table += "<tr><td>" +
x[i].getElementsByTagName("ARTIST")[0].childNodes[0].nodeValue +
"</td><td>" +
x[i].getElementsByTagName("TITLE")[0].childNodes[0].nodeValue +
"</td></tr>";
}
document.getElementById("demo").innerHTML = table;
}</script>
</body>
</html> Display the First CD in an HTML div Element
This example uses a function to display the first CD element in an HTML element with id="showCD":Example
displayCD(0);
function displayCD(i) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
myFunction(this, i);
}
};
xmlhttp.open("GET", "cd_catalog.xml", true);
xmlhttp.send();
}
function myFunction(xml, i) {
var xmlDoc = xml.responseXML;
x = xmlDoc.getElementsByTagName("CD");
document.getElementById("showCD").innerHTML =
"Artist: " +
x[i].getElementsByTagName("ARTIST")[0].childNodes[0].nodeValue +
"<br>Title: " +
x[i].getElementsByTagName("TITLE")[0].childNodes[0].nodeValue +
"<br>Year: " +
x[i].getElementsByTagName("YEAR")[0].childNodes[0].nodeValue;
} Navigate Between the CDs
To navigate between the CDs, in the example above, add a next() and previous() function:Example
function next(){
// display the next CD, unless you are on the last CD if (i < x.length-1) {
i++;
displayCD(i);
}
}
function previous(){
// display the previous CD, unless you are on the first CD if (i > 0) {
i--;
displayCD(i);
}
} Show Album Information When Clicking On a CD
The last example shows how you can display album information when the user clicks on a CD:Example
function displayCD(i) {document.getElementById("showCD").innerHTML =
"Artist: " +
x[i].getElementsByTagName("ARTIST")[0].childNodes[0].nodeValue +
"<br>Title: " +
x[i].getElementsByTagName("TITLE")[0].childNodes[0].nodeValue +
"<br>Year: " +
x[i].getElementsByTagName("YEAR")[0].childNodes[0].nodeValue;
}
