javascript get html file from online link - javascript

i want to call a html online link using xmlhttprequest with javascript, here is my code
but when the code arrive to xmlhttp.open it stopped and does not continue the execution
function loadXMLDoc(size,downloadfromurl) {
var xmlhttp;
if (window.XMLHttpRequest) {
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
} else {
// code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
var temp = xmlhttp.responseText;
}
}
xmlhttp.open("GET", "http://app.arsel.qa/mobileappspeedtest/samples/256.htm?n=" + Math.random(), false);
xmlhttp.send(null);
}

What you are doing is an actual AJAX request to that page.
Cross domain AJAX requests are not allowed by default for security reasons.
However, there are several ways of performing cross domain requests, and you could take a look at how jQuery does it, so you don't have to reinvent the wheel all over again using plain JavaScript. This article should be helpful.
Anyway, if you actually want to crawl that page, there are tons of open source libraries for server side scripting languages like Java, PHP, Node.js, etc that are very useful in gathering the content, parsing the HTML and so on, depending on your needs.

You can use JSONP for overcoming cross domain barrier.
$.ajax({
type:'GET',
dataType:'jsonp',
jsonp: "jsonp",
url:"http://yoururl.com?callback=callbackFunction"
});
function callbackFunction(data){
//you can process the data here
console.log(date)
}

Related

How to hit url in javascript

I want to just hit the url in javascript which will run in background not on frontend.
I had tried this code
var url = "http://yourpage.com";
req = new ActiveXObject("Microsoft.XMLHTTP");
req.open("GET", true);
req.onreadystatechange = callback;
req.send(null);
but it not work for me.
could any one please suggest me how to hit url in javascript.
you should use cross browser JavaScript AJAX code, or better to use jQuery ajax see below sample code
var url = "http://yourpage.com";
var xmlhttp;
if (window.XMLHttpRequest) {
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
} else {
// code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = callback;
xmlhttp.open("GET", url, true);
xmlhttp.send();
I suggest you use either jQuery or AngularJs for sending AJAX requests rather than creating new ActiveXObject objects.
Girish gave you answer using pure javascript. I will give you an example of jQuery usage. Please see code below:
$.get('http://yourpage.com', function(){ /*callback*/ })

Show Save-As window from JSP

I need to write a String in a file on the client side, however as the Internet protocol does not allow that for Security concerns, this is the workaround I did: I have an AJAX request which invokes a JSP that queries a Database to get a String. I need to show the users a "Save-As" dialog and write this String to the local path they specify.
My JavaScript function:
function openReport(id)
{
var url = "../reports/reportsHandler.jsp?id=" + id;
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
//alert(xmlhttp.responseText);
alert("result obtained");
}
}
xmlhttp.open("POST", url, true);
xmlhttp.send();
}
In the JSP, I have something like this:
response.setHeader("Content-Disposition", "attachment;filename=report.xml");
out.println(stringObtainedFromDatabase);
I do not see a Save As dialog while I get the alert saying result obtained. This is the first time I am doing this, could you please tell me if I am doing something wrong?
But, is there a way in JavaScript to show users a Save-As dialog and write the content of "div" tag in a file on the Client system?
Use a regular HTTP request, not an AJAX (XMLHttpRequest) one.
function openReport(id)
{
var url = "../reports/reportsHandler.jsp?id=" + id;
window.location = url;
}
This will send an HTTP GET, not a POST, though it looks like GET is the correct HTTP method to use here anyway, since you're retrieving data and not actually altering anything on the server.

Javascript security stopping me?

I'm pretty sure it's a security issue keeping me from doing this, but I wonder if there's a workaround I don't know of...
I have a script to inject a user's email into the contact DB of my client and it's bombing in IE but working in FF, Chrome (as usual). Just wondering if I can add the server to the trust or something to make it work?
<script type="text/javascript">
window.onload = init;
//Global XMLHTTP Request object
var XmlHttp;
function CreateXmlHttp() {
//Creating object of XMLHTTP in IE
try {
XmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
}
catch (e) {
try {
XmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
catch (ex) {
XmlHttp = null;
}
}
//Creating object of XMLHTTP in Mozilla and Safari
if (!XmlHttp && typeof XMLHttpRequest != "undefined") {
XmlHttp = new XMLHttpRequest();
}
}
function init() {
var x = document.getElementsByName("btnContinue");
x[0].onclick = submitForm;
}
function submitForm() {
var x = document.getElementsByName('Email');
if (x[0].value.length > 0) {
CreateXmlHttp();
XmlHttp.open("POST", "https://app.icontact.com/icp/signup.php", false);
XmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
XmlHttp.send("redirect='http://www.xyz.com/articles.asp?ID=97'&errorredirect='http://www.xyz.com/articles.asp?ID=256'&fields_email=" +
x[0].value + "&listid=123&specialid:123=YP7I&clientid=123&formid=123&reallistid=1&doubleopt=0&Submit=Submit");
}
}
</script>
I'd appreciate any insight.
Thanks!
My first suggestion would be to try creating XMLHttpRequest before ActiveX Objects. IE7 and up DO support AJAX the way other browsers do.
Next, you should use relative paths in the open() method. Although I think form your question it's something that'll need to be able to run on any site? In that case I'd suggest creating a form and an iframe and using the "old" method.
It is a same-origin policy issue. The allow access content headers may be set, but the IE ActiveXObject won't use them. XMLHttpRequests obey the headers and will work on browsers that support them.
See this question:
AJAX Permission Denied On IE?
Though it doesn't look like they found a solution for an IE compatible cross-domain POST...
If you could proxy it through your web server (Make a POST to your server), and have the server make the POST, your problem would be solved.
On new browsers, you can use cross-domain XHR if you can have a special HTTP header on the page you request.
http://ejohn.org/blog/cross-site-xmlhttprequest/
Or you can use dynamic script loading.

XMLHttpRequest status 0 on second load

I am experiencing an interesting issue when I am trying to load some data in .txt format from the same domain using XMLHttpRequest.
I am trying to load the data, parse it and then store it in localStorage
var xmlhttp;
// code for IE7+, Firefox, Chrome, Opera, Safari
if (window.XMLHttpRequest){
xmlhttp=new XMLHttpRequest();
}else{
// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
var temp;
xmlhttp.onreadystatechange=function(){
if (xmlhttp.readyState==4 && xmlhttp.status==200){
temp = xmlhttp.responseText;
}else{
alert("readyState: " + xmlhttp.readyState + "status: " + xmlhttp.status);
}
}
xmlhttp.open("GET","data/somedata.txt", false);
xmlhttp.send();
This code only works if I clean the history and cache; however, on second click of the same link, I would received "Readystate: 4, status 0" for some reason.
Does this has anything to do with localStorage?
if (!localStorage.somedata || localStorage.somedata.count(':') !== somedata.count(':')) {
localStorage.somedata = temp;
}
window.somedata = JSON.parse(localStorage.somedata);
There are two causes of status code of zero.
Making calls from the file protocol.
The page is refreshing/navigating away as the request is being made.
In your case I would assume it is #2. If you are using a button or a link to make the Ajax call, make sure to cancel the click action with either preventDefault or return false.
Sounds like a caching issue. Try either switching to a POST method, or appending a timestamp to the GET request querystring and see if that prevents the caching.
xmlhttp.open("POST", "data/somedata.txt", false);
or:
xmlhttp.open("GET", "data/somedata.txt?" + new Date().valueOf(), false);
Edit: If those don't work, modify your server configuration to send appropriate response headers for that file or type to not cache the response. Ie: Cache-Control: no-cache
Try xmlhttp.abort() before opening a new request.
It's a long shot but worth the try.

Ajax and VbScript: fetching Post variable in test.asp

current i am trying to use ajax for my site ....... because of size of data is not limited i need to use post method for send data to database but the problem is i am unable to fetch the Post variables in the test.asp
here is the script i am using
function SaveData(content )
{
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
msg=xmlhttp.responseText;
alert(msg);
}
}
var para = encodeURIComponent("content="+content)
xmlhttp.open("POST","test.asp",true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
xmlhttp.send(para)
}
and here is test.asp code
t = Request.form("content")
Response.write(t)
please help me solving this problem of fetching the Post method variable in test.asp
if possible any one can share code of jquery ajax with post method in asp classic too that would also be helpful
You need to change this:
var para = encodeURIComponent("content="+content)
into this:
var para = "content=" + encodeURIComponent(content);
The way that it was, you were submitting something like this to the server:
content%3Dtest%20data%20123
With the adjusted line of code, you're submitting something like this, which is as it should be:
content=test%20data%20123
Have you considered using a JavaScript library such as jQuery? A library will abstract away all this unpleasantness:
$.post("test.asp", { 'content': content }, function(data) {
alert("Returned data: " + data);
});

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