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Read information in from a File


CarlosTheDwarf
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My problem is pretty simple - I need to use JavaScript to read text in from a text file, and dont know how to do it.I learned Java first, and to anyone else who knows Java i am basically looking for a substitute for the Scanner class.Also in JavaScript for Dummies it says something in one of the appendixes about accessing Java Packages with JavaScript, but I seem to be unable to grasp how to do it.Thanks a ton,Carlos

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The responseText from AJAX returns the text from any file.I've never heard of Javascript accessing Java packages before.First read the AJAX tutorial: http://w3schools.com/ajax/default.aspJust use AJAX and when using the open() command, put the name of the text file:...xmlHttp.open("GET","file.txt",true);xmlHttp.send(null);...The string of the text file is in the responseText property

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Note that the AJAX trick requires a server-side language. If you're trying to open a file on the user's desktop, JS cannot do that unless the document running the script also lives on the user's desktop. It's a security thang.

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---------Edit: Right, it won't take files from the user's desktop, but it will read any files in its local filesystem without relying on the server or any server-side language.---------It works on the desktop, I've done it myself. AJAX reads the output of files, whether a server side language processes it or not doesn't matter.You can try it yourself.I once tried to make a graphical MIDI file interpretation using AJAX on my desktop, but it was too hard to interpret all the bits, I think I have the guide to MIDI's information in my bookmarks somewhere.AJAX is client-side technology, I just made these files on my desktop to prove it works:file.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html><head><title>Test</title><script type="text/javascript">function GetXmlHttpObject(){var xmlHttp=null;try  {  // Firefox, Opera 8.0+, Safari  xmlHttp=new XMLHttpRequest();  }catch (e)  {  // Internet Explorer  try    {    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");    }  catch (e)    {    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");    }  }return xmlHttp;}window.onload=function() {xmlHttp = GetXmlHttpObject();xmlHttp.onreadystatechange = function() {  if(xmlHttp.readyState == 4) {    document.getElementById('something').innerHTML = xmlHttp.responseText;  }}xmlHttp.open("GET","file.txt",true);xmlHttp.send(null);}</script></head><body><div id="something">a</div></body></html>

file.txt

Hello World!

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