I'm writing a small script that determines if the user is on IE8 or below. If they are, the script should completely empty the document (body and head) and stop any further script executing.
I've played around with document.write() but can only get this working with window.onload. But I want it to execute as soon as it knows the browser version (which is when the script executes).
Example page setup:
<html>
<header>
Some CSS
Some meta
...
</head>
<body>
Page content
<script>
if (IE < 8) { //in reality I have a function to determine this
document.write('You browser is outdate. Please upgrade to view this site.');
}
</script>
<script src="more-scripts"></script>
</body>
</html>
This doesn't work but if I wrap the script in a window.onload it does. But then the page flashes up before the code executes. How can I get this to work?
Rather than using document.write() to print a message, you can use the .innerHTML property of the document.body element to entirely replace the body of the page. For this technique, your browser-check script should go in the head section, not the body (this is usually where scripts like this would go anyway).
<html>
<header>
Some CSS
Some meta
...
<script>
if (IE < 8) { //in reality I have a function to determine this
document.body.innerHTML = "You browser is outdate. Please upgrade to view this site.";
}
</script>
</head>
<body>
Page content
<script src="more-scripts"></script>
</body>
</html>
you could use conditional comments for that:
<!--[if IE 8]>
<script>
document.body.innerHTML = '';
document.write('You browser is outdate. Please upgrade to view this site.');
</script>
<![endif]-->
Related
this is a very odd problem indeed and I hope it's simple. I cannot get a simple select and append to work in my html document, but it works when I'm in the chrome browser console.
<html>
<head>
<script src="https://code.jquery.com/jquery-1.12.3.min.js" integrity="sha256-aaODHAgvwQW1bFOGXMeX+pC4PZIPsvn2h1sArYOhgXQ=" crossorigin="anonymous"></script>
<script src="/js/script.js"></script>
<script>
$('[data-js="works"]').append("hello");
</script>
</head>
<body>
<div data-js="works"></div>
test
</body>
</html>
When I put that line of script in the console, hello appears above test. When I just open the page, test is there alone. I was running a script from this page earlier and when I tried to select an element it didn't work. I then went to inline script to see if it would even work there, no. I've seen if it works from inline script without the imported script, also no. Console has no bug information. I can print from that inline script to my console if I want, but this code still isn't running properly.
Doesn't work with my local httpserver and doesn't work just as a locally opened file.
This is because the script is executed before the page is loaded so the target div does not exist yet.
The solution is to wait for the page to be fully loaded before doing something.
The $ function can be used for this. Give it a callback and it will be executed once the page is loaded.
You can also use window.addEventListener("load", callback); that doesn't need jQuery.
<html>
<head>
<script src="https://code.jquery.com/jquery-1.12.3.min.js" integrity="sha256-aaODHAgvwQW1bFOGXMeX+pC4PZIPsvn2h1sArYOhgXQ=" crossorigin="anonymous"></script>
<script>
$(function(){
$('[data-js=works]').append("hello");
});
</script>
</head>
<body>
<div data-js="works"></div>
test
</body>
</html>
Another solution can be to insert your script at the end of the page. It is not as neat though in my opinion.
<html>
<head>
<script src="https://code.jquery.com/jquery-1.12.3.min.js" integrity="sha256-aaODHAgvwQW1bFOGXMeX+pC4PZIPsvn2h1sArYOhgXQ=" crossorigin="anonymous"></script>
</head>
<body>
<div data-js="works"></div>
test
<script>
$('[data-js=works]').append("hello");
</script>
</body>
</html>
Try the following, hope it will solve your problem
(function($) { // This will solve namespace problem (if any)
// Write your JQuery code here
})(jQuery);
Either you put the .js file at the end of the body or put your JS code between $(document).ready(function(){ //code inside })
I've built a webpage that is basically a main-page with a div that is filled with different pages by using AJAX. This basically works by loading pages into a div by using innerHTML. One problem I ran into was when a page with javascript is loaded into that div all of the other code runs fine; just the javascript doesnt work.
Main-page(index.php):
<html>
<head>
<script type="text/java">
////bunch of functions////
////Ends up that page_request on this instance is 'graph.php'////
document.getElementById('mydiv').innerHTML=page_request.responseText
</script>
</head>
<body>
<div id="mydiv"><div>
</body>
</html>
Child-page(loaded in div(graph.php)):
<html>
<head>
<link rel="stylesheet" href="mystyle.css" type="text/css" media="screen" />
<script src="other_stuff.js"></script>
</head>
<body>
<script>
///bunch of script////
</script>
</body>
</html>
Now when loading the page itself (opening graph.php) I notice that everything works fine; it is just when I import graph.php to index.php through innerHTML into my div it does not work (no errors just nothing is shown). I have read through many other posts and guides and did not come up with any distictive solution; thinks I have seen were:
Put eval() around my code [I saw on a guide that this could lead
to malicious user attacks].
Create the scripts on the main page then just import the data using:
document.createElement() and .parentNode.insertBefore()
Create a listener and call the functions when I open graph.php
And this good example
Even though I am not 100% sure how this example could work because I have php populate information for the javascript to collect and then make my graph on graph.php; so if I put that function into index.php the php will already be loaded so I would have to refresh the page or call them to update information somehow. Just for some context I am ok at php but I am new and struggle with javascript so I do not know what solution would fit my situation or work the best. Any tips/examples would be greatly appreciated, thank you for your time.
From you code snippets it seems you're looking to embed complete pages within the main page. If that's the case, a more straightforward approach would be to use an iframe element instead.
For example:
...
<div id="main-page-container">
<iframe src="some-path/graph.php" scrolling="no" frameborder="no"></iframe>
</div>
...
See reference and usage example.
I would suggest using jQuery's .load() function for this.
Take a look here: jQuery API
Older browsers such as IE8 and below don't allow you insert a string that contains javascript and execute it, in any form.
Take for instance:
function addScriptText(js_code) {
var element = document.createElement("script");
element.innerHTML = js_code;
document.head.appendChild(element);
}
will not work in IE8 and below.
You must use eval to accomplish this:
function addScriptText(js_code) {
window.eval.call(window, js_code);
}
Otherwise you need to dynamically request an external js file such as:
var script = document.createElement("script");
script.type = "text/javascript";
script.src = "externalScript.js";
document.getElementsByTagName("head")[0].appendChild(script);
Note: The page you are loading (page2.html in this example) must be on the same domain as the page that is loading it (page1.html in this example)
Working solution with jQuery:
Page 1:
<!DOCTYPE html>
<html>
<head>
<title>Page 1</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
$(function () {
$("#page2").load("page2.html");
});
</script>
</head>
<body>
<h1>Page 1 Header</h1>
<div id="page2">
</div>
</body>
</html>
Page 2:
<h2>Page 2 Header</h2>
<script type="text/javascript">
alert("Page 2 loaded and javascript executed!");
</script>
i use that tag to alert me when a tag has been shows up
<html>
<head>
</head>
<body>
<script type="text/javascript">
document.getElementsByTagName('iframe')[0].onload = function() {
alert('loaded');
}
</script>
<iframe></iframe>
</body>
</html>
strange , since this code working :
<html>
<head>
</head>
<body>
<iframe></iframe>
<script type="text/javascript">
document.getElementsByTagName('iframe')[0].onload = function() {
alert('loaded');
}
</script>
</body>
</html>
why the Js need to under the tag to work?
what's the problem here?
Because the code in a script tag is executed immediately. And in the first example the iframe doesn't exist at that time. But what you can do is to wrap you code into an onload (for the main page) event. E.g.:
window.onload = function() {
//your code
}
Then it doesn't matter where the code is placed.
Iframe tag does not exist at the moment you are trying to access it.
You may check that by simply alerting array length, like
alert(document.getElementsByTagName('iframe'));
Have you thought about executing your javascript after the page is loaded? You may use some frameworks like jQuery to facilitate crossbrowser issues. Or just put all your javascript code to the very bottom of body.
I want to replace the current script tag with the HTML contents generated by the same script.
That is, my Page is
<html>
<body>
<div>
<script src="myfile1.js"></script>
</div>
<div>
<script src="myfile1.js"></script>
</div>
</body>
</html>
Inside each .js file corresponding html contents are generated. I want to put the contents as the innerHTML of the parent div. But can't set id for the parent div because the page is not static. So the current script tag must be replaced with the HTML content. How can I do this?
For each script tag src is the same. So can't identify with src. These scripts displays
some images with text randomly. Scripts are the same but displays different contents in divs on loading
Please help me
try inside of myfile1.js:
var scripts = document.getElementsByTagName( "script" );
for ( var i = 0; i < scripts.length; ++ i )
{
if ( scripts[i].src == "myfile1.js" )
{
scripts[i].parentNode.innerHTML = "new content";
}
}
This is a great question for those trying to implement a JSONP widget. The objective is to give the user the shortest possible amount of code.
The user prefers:
<script type="text/javscript" src="widget.js"></script>
Over:
<script type="text/javscript" src="widget.js"></script>
<div id="widget"></div>
Here's an example of how to achieve the first snippet:
TOP OF DOCUMENT<br />
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js"></script>
// inside of widget.js
document.write('<div id="widget"></div>');
$(document).ready(function() {
$.getJSON('http://test.com?remote_call=1', function(data) {
$('#widget').html(data);
});
});
<br />BOTTOM OF DOCUMENT
Have a look at: http://alexmarandon.com/articles/web_widget_jquery/ for the correct way to include a library inside of a script.
document.currentScript has been available since 2011 on Firefox and 2013 on Chrome.
document.currentScript documentation at MDN
<!DOCTYPE html>
<meta charset="UTF-8">
<title>currentScript test</title>
<h1>Test Begin</h1>
<script>
document.currentScript.outerHTML = "blah blah";
</script>
<h1>Test End</h1>
Unfortunately a running JavaScript file is not aware of where it is running. If you use document.write() in the script, the write function will take place wherever the script runs, which would be one way to accomplish what you want, but without replacing the contents or being able to perform any actions on the enclosing DIV.
I can't really envisage a situation where you'd have such stringent restrictions on building a page - surely if the page is dynamic you could generate identifiers for your DIV elements, or load content in a more traditional manner?
Why not use Smarty?
http://www.smarty.net/
You can use javascript in Smarty templates, or just use built-in functions.
Just take a look at http://www.smarty.net/crash_course
poof -- old answer gone.
Based on your last edit, here's what you want to do:
<html>
<head>
<!-- I recommend getting this from Google Ajax Libraries
You don't need this, but it makes my answer way shorter -->
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
$(document).ready(function(){
function getRandomContent(){
// I expect this is the contents of your current script file.
// just package it into a function.
var rnd = Math.random();
return "[SomeHtml]";
}
$('.random').each(idx, el){
$(this).html(getRandomHtmlContent());
});
});
</script>
</head>
<body>
<div class="random">
</div>
<div class="random">
</div>
</body>
</html>
If you don't mind the script tag remaining in place you can use something as simple as document.write().
myfile1.js:
document.write("<p>some html generated inline by script</p>");
It will do exactly what you need.
When you execute following example using Firefox 3:
<html>
<head>
<script language="javascript" type="text/javascript">
<!--
function openWindow(){
var w = window.open('', 'otherWin', 'width=600,height=600');
w.document.write(document.getElementsByTagName("html")[0].innerHTML);
w.document.close();
reportLinks(w.document.links);
}
function reportLinks(links){
var report = 'links: '+links.length;
for (var i=0;i<links.length;i++){
report += '\n (link='+links[i].href+')';
}
alert(report);
}
//-->
</script>
</head>
<body>
<p>Open Same Content and Show Links Report</p>
<p>Show Links Report</p>
</body>
</html>
You will see that both the number of links shown when clicking on 'Show Links Report' as when clicking on 'Open Same Content and Show Links Report' will be 2. However when having an external JavaScript file reference from this page the behavior seems different (just make an empty file some.js if you want). When clicking 'Open Same Content and Show Links Report' the number of links will be 0.
<html>
<head>
<script language="javascript" type="text/javascript" src="some.js"></script>
<script language="javascript" type="text/javascript">
<!--
function openWindow(){
var w = window.open('', 'otherWin', 'width=600,height=600');
w.document.write(document.getElementsByTagName("html")[0].innerHTML);
w.document.close();
reportLinks(w.document.links);
}
function reportLinks(links){
var report = 'links: '+links.length;
for (var i=0;i<links.length;i++){
report += '\n (link='+links[i].href+')';
}
alert(report);
}
//-->
</script>
</head>
<body>
<p>Open Same Content and Show Links Report</p>
<p>Show Links Report</p>
</body>
</html>
It is probably a matter of loading the page and the moment that reportLinks executed exactly. I assume that the external some.js is added that the document is not completely build up. Is there a way that I can register this reportLinks call for onload event so that I can be sure that document.links is complete?
By the way the example works fine in both cases with Google Chrome.
(added after answer1)
As suggested by Marcel K. I rewrote the example, added also the code the way I really would like to have the thing going. And now testing it, and this simple example seems to work with Firefox and with Chrome.
<html>
<head>
<script type="text/javascript" src="some.js"></script>
<script type="text/javascript">
<!--
function openWindow(){
var w = window.open('', 'otherWin', 'width=600,height=600');
w.document.write('<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">\n<html>\n'+
document.getElementsByTagName("html")[0].innerHTML+'\n</html>');
w.onload=function(){
reportLinks(w.document.links);
};
w.document.close();
}
function reportLinks(links){
var report = 'links: '+links.length;
for (var i=0;i<links.length;i++){
report += '\n (link='+links[i].href+')';
}
alert(report);
}
//-->
</script>
</head>
<body>
<p>Open Same Content and Show Links Report</p>
<p>Show Links Report</p>
</body>
</html>
I had hoped with this simple example to show a simple case of the actual code I am writing. A print preview screen of complicated html in which I want to disable all hrefs once opened. But in that one the onload handler is never called... How can I register an onload handler in this case in the most robust way?
Many thanks,
Marcel
As I said in a comment, this is a very strange issue. But I think it happens because the inclusion of an external script causes a delay in page rendering (of the new page) and its DOM might not be ready to inspect.
My suspicion is supported by the fact that adding the (new) defer attribute seems to solve this issue:
This Boolean attribute is set to indicate to a browser that the script is meant to be executed after the document has been parsed.
The defer attribute can be set on the original page, as you want an exact copy of it. You can set it if it doesn't matter where a script is being included (e.g., when using document.write in your included file it does matter at which place you include it).
As defer is a Boolean attribute, it is activated when it is simply present (defer) or (when using XHTML) set to itself (defer="defer"). In your case, the script inclusion would read:
<script type="text/javascript" src="some.js" defer></script>
Update regarding your update: you should still insert a Doctype in the main page (consider using the HTML 5 one).
And I think the way you attached your onload event is the best you can do.
But considering the goal you want to achieve (a print preview without hyperlinks): you can also use the "print" media attribute and style hyperlinks like text; that's way more easy than the thing you are doing and it works when JavaScript is disabled.
The only way I could make the example above work portable over Firefox, Chrome and IE is by registering the onload listener through inlined JavaScript in the HTML loaded in the popup window. Following example code shows how.
<html>
<head>
<script type="text/javascript" src="script.js"></script>
</head>
<body>
<p>Open Same Content and Show Links Report</p>
<p>Show Links Report</p>
</body>
</html>
This page uses a script in script.js file. Following shows the content of that file.
function openWindow(){
var w = window.open('', 'otherWin', 'width=600,height=600');
w.document.write(
'<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">\n<html>\n'+
document.getElementsByTagName("html")[0].innerHTML+
'\n <script type="text/javascript">\n'+
' function addOnloadListener(listener){\n'+
' if (window.addEventListener) {\n'+
' window.addEventListener("load", listener, false);\n'+
' } else {\n'+
' window.attachEvent("onload",listener);\n'+
' }\n'+
' }\n'+
' addOnloadListener(function(){reportLinks(document.links);});\n'+
' </script>\n'+
'</html>');
w.document.close();
}
function reportLinks(links){
var report = 'links: '+links.length;
for (var i=0;i<links.length;i++){
report += '\n (link='+links[i].href+')';
}
alert(report);
}
When putting the function addOnloadListener directly in the JavaScript file (not inlined in the page) it doesn't work in IE6 because, I believe, it cannot handle the order of script entries correctly. When addOnloadListener was not inlined the inlined call to addOnloadListener didn't work, it simply couldn't find the function in the earlier:
<script type="text/javascript" src="script.js"></script>
The code is only a simple example that doesn't really do a lot. I used it for disabling all links in a print preview popup page.
A simpler way to register an onload listener for a popup window portable over browser is always welcome.
Thanks,
Marcel