CSD 340 (Blum) 1

Making and Reading from XML Files

Chapter 14 of Beginning JavaScript (Paul Wilton)

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File/New/File

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Choose an XML File template and click Open

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Start of XML File

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Design tags and enter data.

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In the Data view

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Save file.

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Saving File

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Enter more data and save

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State Capital Quiz design

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Code for reading XML file for State data and initializing arrays

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Declare and instantiate arrays for state names and capitals

var QUIZ_SIZE=5;

var MyStateName = new Array(50);

var MyStateCapital = new Array(50);

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//loads data from xml file into the arrays (IE only)

function LoadStateArray()

{

var xmlDoc = new ActiveXObject("Microsoft.XMLDOM"); xmlDoc.async = false;

xmlDoc.load("States.xml");

Declare and instantiate and ActiveX that can parse an XML file.

Setting the async property to false means that the code has to wait for a response. Since the next line of code is about loading the xml file, that is what we are waiting for.

Load the XML file.

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Webopedia definition of ActiveX

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Webopedia definition of asynchronous

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for(i=0; i< xmlDoc.getElementsByTagName("state").length; i++) { MyStateName[i] = xmlDoc.getElementsByTagName("state")

[i].getElementsByTagName("stateName")[0].firstChild.nodeValue; MyStateCapital[i] = xmlDoc.getElementsByTagName("state")

[i].getElementsByTagName("stateCapital")[0].firstChild.nodeValue; } //end of for loop} //end of function

Loop through the “state” elements.

Initialize the elements of the arrays from the data in the XML file.

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Whatis definition of tree

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References

• Beginning JavaScript, Paul Wilton

• http://www.webopedia.com

• http://www.whatis.com