XML Parse Javascript

[karthikin]

Hi Guys, how can i parse the null child node? In one <CONTACT> there is no value for gmail but it another <CONTACT> it has value for gmail. How can parse these null child nodes? Please help me to parse this xml file in javascript with some code. Thanks guys...

<?xml version="1.0" encoding="UTF-8"?><CONTACTS><CONTACT><PDE-Identity>N65539</PDE-Identity><FirstName>Arun_niit</FirstName><LastName>Arun_niit</LastName><gmail/><yahoo>nura@yahoo.co.in</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65593</PDE-Identity><FirstName>Rangarajkarthik</FirstName><LastName>karthik Rangaraj</LastName><gmail>kart26@gmail.com</gmail><yahoo>karthikraj@yahoo.com</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT></CONTACTS>

[jeffman]

When an element has content, you find it in element.childNodes[0].nodeValue. (I use the word element to mean the parentNode you are accessing. You will call it anything you want.)If you try that with an element that has no content, you get an error. I guess that is the problem you're asking about. The trick is to realize where the error occurs.The error does not occur when you try to reference the nodeValue.The error occurs when you try to reference the childNode.The solution is to test the length of the childNodes. If the length is 0, childNodes[0] does not exist. So don't try to reference it. Reference it only if the length is greater than 0. Something like this:

if (element.childNodes.length > 0) {   return element.childNodes[0].nodeValue;}else {   return "";}

[karthikin]

When an element has content, you find it in element.childNodes[0].nodeValue. (I use the word element to mean the parentNode you are accessing. You will call it anything you want.)If you try that with an element that has no content, you get an error. I guess that is the problem you're asking about. The trick is to realize where the error occurs.The error does not occur when you try to reference the nodeValue.The error occurs when you try to reference the childNode.The solution is to test the length of the childNodes. If the length is 0, childNodes[0] does not exist. So don't try to reference it. Reference it only if the length is greater than 0. Something like this:

function init(){var str=x[i].getElementsByTagName("PDE-Identity")[0].childNodes[0].nodeValue;document.getElementById("pde").value=str;var str=x[i].getElementsByTagName("FirstName")[0].childNodes[0].nodeValue;document.getElementById("fname").value=str; var str=x[i].getElementsByTagName("LastName")[0].childNodes[0].nodeValue;document.getElementById("lname").value=str; var str=x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue;document.getElementById("gmaail").value=str; var str=x[i].getElementsByTagName("yahoo")[0].childNodes[0].nodeValue;document.getElementById("yaahoo").value=str; var str=x[i].getElementsByTagName("alcatel-lucent")[0].childNodes[0].nodeValue;document.getElementById("alcaatel-lucent").value=str;   var str=x[i].getElementsByTagName("URL")[0].childNodes[0].nodeValue;document.getElementById("facebook").value=str; var str=x[i].getElementsByTagName("Facebook-ID")[0].childNodes[0].nodeValue;document.getElementById("fid").value=str; } 

[jeffman]

In the code I showed you, replace element with x.getElementsByTagName("gmail")[0]That's the short answer.The better answer is to build a function using my code and pass x.getElementsByTagName("gmail")[0] to the function. This is a better answer because it will not be limited to your gmail problem. You will be able to use the function whenever you need to get a nodeValue.

[karthikin]

In the code I showed you, replace element with x.getElementsByTagName("gmail")[0]That's the short answer.The better answer is to build a function using my code and pass x.getElementsByTagName("gmail")[0] to the function. This is a better answer because it will not be limited to your gmail problem. You will be able to use the function whenever you need to get a nodeValue.

Ok. Thanks I'm gonna work on it. Thank you..

[karthikin]

Ok. Thanks I'm gonna work on it. Thank you..

HI, i tried in this way, it's not working.

if (x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue.childNodes.length > 0) {   return x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue.childNodes[0].nodeValue;}else {   return "";}}

I couldn't pass the output to my text box. Please help me to write the function. Thank u.

[jeffman]

Add this function to your script. It should be OUTSIDE your init() function:

function get_node_value (element) {   if (element.childNodes.length > 0) {	  return element.childNodes[0].nodeValue;   }   else {	  return "";   }}

In your init() function, replace this code:

var str=x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue;

with this code:

var str = get_node_value(x[i].getElementsByTagName("gmail")[0] );

Now your problem is solved AND you have a function to use whenever you want to get the value of a text node without generating an error.

[karthikin]

HI, i tried in this way, it's not working.

if (x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue.childNodes.length > 0) {   return x[i].getElementsByTagName("gmail")[0].childNodes[0].nodeValue.childNodes[0].nodeValue;}else {   return "";}}

I couldn't pass the output to my text box. Please help me to write the function. Thank u.

Thank you it's works perfectly. I have one more problem with the dynamic menu list. I would like to have <PDE-Identity> values in my menu-list, when we select the "PDE-Identity" from menu list it should display all the values in the text box. Please explain to me how can i do this... Thanks a lot for you help and support.This is my menu-list code:

<label control="" value="Select PDE-ID:"/><menulist id="List" oncomman="">               <menupopup  id="Popup">               </menupopup></menulist> 

I found this to do the menulist but i have a hard time in understand this: https://developer.mozilla.org/en/DOM/element.getElementsByTagNameThis is the java-script:

var objNodeList = objXMLDoc.getElementsByTagName("PDE-Identity");   for (var i=0; i<objNodeList.length; i++){            var menuPopup=document.getElementById('Popup');                                      var menu1=document.createElement("menuitem");                        menu1.setAttribute("label",'objNodeList');                       menuPopup.appendChild(menu1);} var x = objXMLDoc.getElementsByTagName("CONTACT");i=-1; function init(){ var str = get_node_value(x[i].getElementsByTagName("PDE-Identity")[0] );document.getElementById("pde").value=str; var str = get_node_value(x[i].getElementsByTagName("FirstName")[0] );document.getElementById("fname").value=str;  var str = get_node_value(x[i].getElementsByTagName("LastName")[0] );document.getElementById("lname").value=str; var str = get_node_value(x[i].getElementsByTagName("gmail")[0] );document.getElementById("gmaail").value=str; var str = get_node_value(x[i].getElementsByTagName("yahoo")[0] );document.getElementById("yaahoo").value=str;  var str = get_node_value(x[i].getElementsByTagName("alcatel-lucent")[0] );document.getElementById("alcaatel-lucent").value=str;    var str = get_node_value(x[i].getElementsByTagName("URL")[0] );document.getElementById("facebook").value=str;   var str = get_node_value(x[i].getElementsByTagName("Facebook-ID")[0] );document.getElementById("fid").value=str; }function get_node_value (element) {   if (element.childNodes.length > 0) {      return element.childNodes[0].nodeValue;   }   else {      return "";   }}

code:

[jeffman]

Please ask a more specific question.

[karthikin]

Please ask a more specific question.

I have a menu list in my XUL and how can I list all the <PDE-Identity> values in to my menu list dynamically as a menu item from XML file? If we select the menu item(PDE-Identity values=N65539) it should display the rest of the values in my text boxes. Please help me and sorry for my poor English.

<label control="" value="Select PDE-ID:"/><menulist id="menulist" oncomman="">               <menupopup  id="populate">               </menupopup></menulist>     <rows >      <row>        <label value="PDE-Identity"/>        <textbox id="pde" value=""/>      </row>      <row>        <label value="FirstName"/>        <textbox id="fname" value=""/>      </row>      <row>        <label value="LastName"/>        <textbox id="lname" value=""/>      </row>      <row>          <label value="Gmail"/>        <textbox id="gmaail" value=""/>      </row>      <row>          <label value="Yahoo"/>        <textbox id="yaahoo" value=""/>      </row>      <row>          <label value="Alcatel-Lucent"/>        <textbox id="alcaatel-lucent" value="" />      </row>      <row>          <label value="URL"/>        <textbox id="facebook" value="" />      </row>      <row>          <label value="Facebook-ID"/>        <textbox id="fid" value="" />      </row>    </rows> 

My xml code:

<?xml version="1.0" encoding="UTF-8"?><CONTACTS><CONTACT><PDE-Identity>N65539</PDE-Identity><FirstName>Arun_niit</FirstName><LastName>Arun_niit</LastName><gmail/><yahoo>nurce@yahoo.co.in</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65553</PDE-Identity><FirstName>FodenBen'</FirstName><LastName>Ben' Foden</LastName><gmail/><yahoo/><alcatel-lucent/><URL>http://www.facebook.com/profile.php?id=100002440474277</URL><Facebook-ID>100002440474277</Facebook-ID></CONTACT><CONTACT><PDE-Identity>N65565</PDE-Identity><FirstName>GhorbelMahmoud</FirstName><LastName>Mahmoud Ghorbel</LastName><gmail/><yahoo/><alcatel-lucent>mahmoud.bel@alcatel-lucent.com</alcatel-lucent><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65579</PDE-Identity><FirstName>keyankarthik</FirstName><LastName>karthik keyan</LastName><gmail/><yahoo>karthse@yahoo.co.in</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65593</PDE-Identity><FirstName>Rangarajkarthik</FirstName><LastName>karthik Rangaraj</LastName><gmail>kart2006@gmail.com</gmail><yahoo>karthrangaraj@yahoo.com</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65612</PDE-Identity><FirstName>ReddyAkky</FirstName><LastName>Akky Reddy</LastName><gmail>akkddych@gmail.com</gmail><yahoo/><alcatel-lucent/><URL/><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65626</PDE-Identity><FirstName>SandfordFrankie</FirstName><LastName>Frankie Sandford</LastName><gmail/><yahoo/><alcatel-lucent/><URL>http://www.facebook.com/FrankieSandfordApprovedPage</URL><Facebook-ID/></CONTACT><CONTACT><PDE-Identity>N65637</PDE-Identity><FirstName>TheSatsRochelle</FirstName><LastName>Rochelle TheSats</LastName><gmail/><yahoo/><alcatel-lucent/><URL>http://www.facebook.com/profile.php?id=100002487211054</URL><Facebook-ID>100002487211054</Facebook-ID></CONTACT><CONTACT><PDE-Identity>N65649</PDE-Identity><FirstName>KumarVeera</FirstName><LastName>Veera_Kumar</LastName><gmail>KUMAa81@gmail.com</gmail><yahoo>KUMag@yahoo.com</yahoo><alcatel-lucent/><URL/><Facebook-ID/></CONTACT></CONTACTS>

[jeffman]

This is not a specific question. It does not have many words, but the process you are describing is a big one. Please discover a small thing in your code that you do not understand. Ask about that.

[karthikin]

This is not a specific question. It does not have many words, but the process you are describing is a big one. Please discover a small thing in your code that you do not understand. Ask about that.

OK. I'm sorry...Here is the detailed problem....This is my menulist

<label control="" value="Select PDE-ID:"/><menulist id="menulist" oncomman="">               <menupopup  id="populate">               </menupopup></menulist> 

This is my java script:

var objNodeList = objXMLDoc.getElementsByTagName("PDE-Identity");   for (var i=0; i<objNodeList.length; i++){            var menuPopup=document.getElementById('populate');                                      var menu1=document.createElement("menuitem");                        menu1.setAttribute("label",'objNodeList');                       menuPopup.appendChild(menu1);}

Here i'm trying to get the "getElementsByTagName("PDE-Identity");" to my menu-list. I couldn't get the values of the PDE-Identity in my menu-list.Thank you.

[karthikin]

Hi, do you have any suggestion? Please give me some idea...I'm waiting for your reply. Thanks for your support.

[jeffman]

If you use the function I showed you before, you can get the values of all the PDE-Identity elements like this:

val = get_node_value(objNodeList[i] );

That should go somewhere in your for-loop. I'm not sure where. Maybe here?

val = get_node_value(objNodeList[i] );menu1.setAttribute("label", val);

[karthikin]

Thank you for being patient with me and for your help. It works! I used you code and put it in my for loop. Like this:

var objNodeList = objXMLDoc.getElementsByTagName("PDE-Identity");   for (var i=0; i<objNodeList.length; i++){			var menuPopup=document.getElementById('populate');				val = get_node_value(objNodeList[i] );			   					 var menu1=document.createElement("menuitem");					   menu1.setAttribute("label", val);					   menuPopup.appendChild(menu1);}

Do you have any suggestion/idea to get information all the <contact> when we select the "PDE-Identity" from the menu-list? Thank you very much.

[jeffman]

Save yourself some work this way. After this line of code:

menu1.setAttribute("label", val);

Add this line of code:

menu1.setAttribute("myIndex", i);

myIndex is not a standard attribute. I invented it to save time. The event handler that looks at the value of the menu item's value attribute can also look at the value of the myIndex attribute. myIndex is an index of the correct CONTACT element in your XML document. You can get a reference to the correct CONTACT element like this:

var i = something.myIndex;var myContactElement = objXMLDoc.getElementsByTagName("CONTACT")[i];

You will have to replace "something" with a reference to the correct menu item. I don't know how you identify that because I can't see that part of your code.

[karthikin]

I'm sorry to bother you too much 'cause it's confusing to me a little bit. Please give me some more detailed information. Thank you very much.Her is my complete code, I have written this code in XUL file.

<?xml version="1.0"?><?xml-stylesheet href="chrome://global/skin/" type="text/css"?><window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" >			    <grid>	<columns>	  <column flex="1"/>	  <column flex="4"/>	   <column flex="4"/>	  <column flex="4"/>	   <column flex="4"/>	</columns> 	<rows>	  <row><label control="" value="Select PDE-ID:"/><menulist id="menulist" oncommand="display()"> >			   <menupopup  id="populate">			   </menupopup></menulist> 	  </row>	</rows></grid><groupbox>	  <label control="" accesskey="" value=""/>  <grid>	<columns>	  <column flex="1"/>	  <column flex="4"/>		<column flex="4"/>		<column flex="4"/><column flex="4"/>	</columns> 	<rows >	  <row>		<label value="PDE-Identity"/>		<textbox id="pde" value=""/>	  </row>	  <row>		<label value="FirstName"/>		<textbox id="fname" value=""/>	  </row>	  <row>		<label value="LastName"/>		<textbox id="lname" value=""/>	  </row>	  <row>		  <label value="Gmail"/>		<textbox id="gmaail" value=""/>	  </row>	  <row>		  <label value="Yahoo"/>		<textbox id="yaahoo" value=""/>	  </row>	  <row>		  <label value="Alcatel-Lucent"/>		<textbox id="alcaatel-lucent" value="" />	  </row>	  <row>		  <label value="URL"/>		<textbox id="facebook" value="" />	  </row>	  <row>		  <label value="Facebook-ID"/>		<textbox id="fid" value="" />	  </row>	</rows>  </grid><label  value=""/><grid flex="1">	<columns>		<column flex=""/>	<hbox align="center" >		<button id="previous"   label="Previous"   oncommand="previous()" />		<button id="next"	   label="Next"	   oncommand="next()"/>		<button id="save"	   label="Save"	   onclick="write()"/>		<button id="reset"	  label="Reset"	  onclick="reset()"/>		  	</hbox></columns></grid></groupbox>	  <separator/><text value="© 2011"/><separator/>  <script type="application/x-javascript"><![CDATA[    var objXMLDoc = document.implementation.createDocument('','doc',null);var objXMLHTTP = new XMLHttpRequest(); objXMLHTTP.open("GET", "file://D:/xmlparserinxul/finalversion2.xml", false);objXMLHTTP.send(null);objXMLDoc = objXMLHTTP.responseXML;	var objNodeList = objXMLDoc.getElementsByTagName("PDE-Identity");   for (var i=0; i<objNodeList.length; i++){			var menuPopup=document.getElementById('populate');				val = get_node_value(objNodeList[i] );			   					 var menu1=document.createElement("menuitem");					   menu1.setAttribute("label", val);					   menuPopup.appendChild(menu1);}function display(){} var x = objXMLDoc.getElementsByTagName("CONTACT");i=-1; function init(){ var str = get_node_value(x[i].getElementsByTagName("PDE-Identity")[0] );document.getElementById("pde").value=str; var str = get_node_value(x[i].getElementsByTagName("FirstName")[0] );document.getElementById("fname").value=str;  var str = get_node_value(x[i].getElementsByTagName("LastName")[0] );document.getElementById("lname").value=str; var str = get_node_value(x[i].getElementsByTagName("gmail")[0] );document.getElementById("gmaail").value=str; var str = get_node_value(x[i].getElementsByTagName("yahoo")[0] );document.getElementById("yaahoo").value=str;  var str = get_node_value(x[i].getElementsByTagName("alcatel-lucent")[0] );document.getElementById("alcaatel-lucent").value=str;    var str = get_node_value(x[i].getElementsByTagName("URL")[0] );document.getElementById("facebook").value=str;   var str = get_node_value(x[i].getElementsByTagName("Facebook-ID")[0] );document.getElementById("fid").value=str; }function get_node_value (element) {   if (element.childNodes.length > 0) {	  return element.childNodes[0].nodeValue;   }   else {	  return "";   }} function next(){ if (i<x.length-1)  {  i++;  init();   }} function previous(){/*document.getElementById("pde").value='';document.getElementById("fname").value='';document.getElementById("lname").value='';  document.getElementById("gmaail").value='';document.getElementById("yaahoo").value='';document.getElementById("alcaatel-lucent").value='';document.getElementById("facebook").value='';document.getElementById("fid").value=''; */ if (i>0)  {   i--;  init();   }}function reset(){document.getElementById("pde").value='';document.getElementById("fname").value='';document.getElementById("lname").value='';document.getElementById("gmaail").value='';document.getElementById("yaahoo").value='';document.getElementById("alcaatel-lucent").value='';document.getElementById("facebook").value='';document.getElementById("fid").value=''; } function save(){Components.utils.import("resource://gre/modules/NetUtil.jsm");Components.utils.import("resource://gre/modules/FileUtils.jsm"); // file is nsIFile, data is a string // You can also optionally pass a flags parameter here. It defaults to// FileUtils.MODE_WRONLY | FileUtils.MODE_CREATE | FileUtils.MODE_TRUNCATE;var ostream = FileUtils.openSafeFileOutputStream(file) var converter = Components.classes["@mozilla.org/intl/scriptableunicodeconverter"].				createInstance(Components.interfaces.nsIScriptableUnicodeConverter);converter.charset = "UTF-8";var istream = converter.convertToInputStream(data); // The last argument (the callback) is optional.NetUtil.asyncCopy(istream, ostream, function(status) {  if (!Components.isSuccessCode(status)) {	// Handle error!	return;  }   // Data has been written to the file.}); }  ]]></script> </window>

[jeffman]

Where is the code that executes when the user selects a menu item?

[karthikin]

Hi, i'm sorry. I have no idea how to start writing function when we select a menu item. I need some guidance to proceed. Thank you very much.

[jeffman]

Has it occurred to you that you really don't know enough to work on this project? I think you have wasted enough of my time.Read about events.Read about functions.Read about JavaScript.

[karthikin]

I'm sorry if i wasted your time unnecessarily. I completely forgot to include the function in the menu-list. <menulist id="menulist" oncommand="display()"> I'm started working on it. I know how to make event function in the menu-list. I'm sure i'll get back to you with the code to select menu item. I'm a slow learner and I never worked on programming much. I'm sure i'll be able to do this and I already started working on it.I'll get back to you tomorrow. Please stand by me. Thank you very much.

[karthikin]

@Deirdre's Dad: I just thought that if i have more than 5O contacts in xml file using it'll be hard to display in the menu list. So i would like to have a search field to type the PDE-ID to display the contact information.

    <hbox align="center" >    <label value="Type PDE-ID to Search"/>      <textbox id="find" type="search"/>       <button label="Search" oncommand="search();"/>       <button label="Clear" oncommand="clear();"/>           </hbox>

function search(){var x = document.getElementById("find").value;alert('hi');} function clear(){document.getElementById("find").value='';}

I hope now you can assist me like the other day. This time i have learnt as much as i could. Please help me... Thank you.

[karthikin]

@Deirdre's Dad: I'm waiting for you reply. Thank you.

[jeffman]

I still think you need to master some more basics before you work on this project. I'm sorry if that seems uncaring, but this has turned into a frustrating experience for me. Maybe someone else can help you.

[karthikin]

I still think you need to master some more basics before you work on this project. I'm sorry if that seems uncaring, but this has turned into a frustrating experience for me. Maybe someone else can help you.

@Deirdre's Dad: You are right. I should learn basics properly. This is the first time i'm working on a real project and it's a big experience for me. I'm struggling a lot. I hope i'll be able to do it with some help.I'm sorry that I have bothered you too much. You have helped me a lot.Thank you very much.