Basically what the title says. I'm making a game and most of it is in js. My concern is that the player stats are all just variables in its object and they are easy to change in the browser console(e.g. player.hitpoints = 1000;).
Is there any way to hide certain objects/variables from being editable in the browser console?
JavaScript is clients side scripting language, that means that it is interpreter on the client's computer and he can do or change whatever he wants. You can uglify and minimize your code for obfuscation the code, but it won't prevent the user from changing it.
I just google "obfuscation javascript code online" and I found this link with a good example of before and after the obfuscation process - here
The other answers have already explained obfuscation and the inherent limitations of client side JavaScript. They are correct and relevant, but don't directly address the question.
To make it impossible¹ to access a variable through the browser console, you need to make it into a local variable inside a function. For example, instead of:
var player = {hitpoints: 100};
// game logic here
You would do:
(function() {
var player = {hitpoints: 100};
// game logic here
})();
This creates an anonymous function, and then immediately calls it, the so-called IIFE. Now player is no longer global (i.e. a property on the window object), but exists only within this function.
¹ It can still be done through the debugger, but it's a lot harder than just copying and pasting some commands.
You can use JWT to make immutable data that don't change very often. For your case, I would recommend storing the state on the server.
You can minify/uglify your code to make it trickier for someone to modify it, but the most important part would be to validate everything server-side. If their hitpoints equal 10 one second and 10000 the next, obviously something would be fishy and the server could prevent itself from broadcasting that out to the other players -- essentially isolating the ne'er-do-well to their own PC.
Identifiers declared with let and const do have block scope. So if your variables are not declared with var then use a block statement.
Example:
code:{
//your code...
}
code: {
let hitpoint = 12;
let kill = function() {
hitpoint -= 12;
}
//function kill(){} is accessible from outside
//let kill = function(){} is not accessible from outside
console.log("From inside:", hitpoint)
}
try {
console.log("From outside:", hitpoint)
} catch (err) {
console.log("From outside:", "It gives an error. So you can't access it from the console or anywhere outside the code")
}
So apparently because of the recent scams, the developer tools is exploited by people to post spam and even used to "hack" accounts. Facebook has blocked the developer tools, and I can't even use the console.
How did they do that?? One Stack Overflow post claimed that it is not possible, but Facebook has proven them wrong.
Just go to Facebook and open up the developer tools, type one character into the console, and this warning pops up. No matter what you put in, it will not get executed.
How is this possible?
They even blocked auto-complete in the console:
I'm a security engineer at Facebook and this is my fault. We're testing this for some users to see if it can slow down some attacks where users are tricked into pasting (malicious) JavaScript code into the browser console.
Just to be clear: trying to block hackers client-side is a bad idea in general;
this is to protect against a specific social engineering attack.
If you ended up in the test group and are annoyed by this, sorry.
I tried to make the old opt-out page (now help page) as simple as possible while still being scary enough to stop at least some of the victims.
The actual code is pretty similar to #joeldixon66's link; ours is a little more complicated for no good reason.
Chrome wraps all console code in
with ((console && console._commandLineAPI) || {}) {
<code goes here>
}
... so the site redefines console._commandLineAPI to throw:
Object.defineProperty(console, '_commandLineAPI',
{ get : function() { throw 'Nooo!' } })
This is not quite enough (try it!), but that's the
main trick.
Epilogue: The Chrome team decided that defeating the console from user-side JS was a bug and fixed the issue, rendering this technique invalid. Afterwards, additional protection was added to protect users from self-xss.
I located the Facebook's console buster script using Chrome developer tools. Here is the script with minor changes for readability. I have removed the bits that I could not understand:
Object.defineProperty(window, "console", {
value: console,
writable: false,
configurable: false
});
var i = 0;
function showWarningAndThrow() {
if (!i) {
setTimeout(function () {
console.log("%cWarning message", "font: 2em sans-serif; color: yellow; background-color: red;");
}, 1);
i = 1;
}
throw "Console is disabled";
}
var l, n = {
set: function (o) {
l = o;
},
get: function () {
showWarningAndThrow();
return l;
}
};
Object.defineProperty(console, "_commandLineAPI", n);
Object.defineProperty(console, "__commandLineAPI", n);
With this, the console auto-complete fails silently while statements typed in console will fail to execute (the exception will be logged).
References:
Object.defineProperty
Object.getOwnPropertyDescriptor
Chrome's console.log function (for tips on formatting output)
I couldn't get it to trigger that on any page. A more robust version of this would do it:
window.console.log = function(){
console.error('The developer console is temp...');
window.console.log = function() {
return false;
}
}
console.log('test');
To style the output: Colors in JavaScript console
Edit Thinking #joeldixon66 has the right idea: Disable JavaScript execution from console « ::: KSpace :::
Besides redefining console._commandLineAPI,
there are some other ways to break into InjectedScriptHost on WebKit browsers, to prevent or alter the evaluation of expressions entered into the developer's console.
Edit:
Chrome has fixed this in a past release. - which must have been before February 2015, as I created the gist at that time
So here's another possibility. This time we hook in, a level above, directly into InjectedScript rather than InjectedScriptHost as opposed to the prior version.
Which is kind of nice, as you can directly monkey patch InjectedScript._evaluateAndWrap instead of having to rely on InjectedScriptHost.evaluate as that gives you more fine-grained control over what should happen.
Another pretty interesting thing is, that we can intercept the internal result when an expression is evaluated and return that to the user instead of the normal behavior.
Here is the code, that does exactly that, return the internal result when a user evaluates something in the console.
var is;
Object.defineProperty(Object.prototype,"_lastResult",{
get:function(){
return this._lR;
},
set:function(v){
if (typeof this._commandLineAPIImpl=="object") is=this;
this._lR=v;
}
});
setTimeout(function(){
var ev=is._evaluateAndWrap;
is._evaluateAndWrap=function(){
var res=ev.apply(is,arguments);
console.log();
if (arguments[2]==="completion") {
//This is the path you end up when a user types in the console and autocompletion get's evaluated
//Chrome expects a wrapped result to be returned from evaluateAndWrap.
//You can use `ev` to generate an object yourself.
//In case of the autocompletion chrome exptects an wrapped object with the properties that can be autocompleted. e.g.;
//{iGetAutoCompleted: true}
//You would then go and return that object wrapped, like
//return ev.call (is, '', '({test:true})', 'completion', true, false, true);
//Would make `test` pop up for every autocompletion.
//Note that syntax as well as every Object.prototype property get's added to that list later,
//so you won't be able to exclude things like `while` from the autocompletion list,
//unless you wou'd find a way to rewrite the getCompletions function.
//
return res; //Return the autocompletion result. If you want to break that, return nothing or an empty object
} else {
//This is the path where you end up when a user actually presses enter to evaluate an expression.
//In order to return anything as normal evaluation output, you have to return a wrapped object.
//In this case, we want to return the generated remote object.
//Since this is already a wrapped object it would be converted if we directly return it. Hence,
//`return result` would actually replicate the very normal behaviour as the result is converted.
//to output what's actually in the remote object, we have to stringify it and `evaluateAndWrap` that object again.`
//This is quite interesting;
return ev.call (is, null, '(' + JSON.stringify (res) + ')', "console", true, false, true)
}
};
},0);
It's a bit verbose, but I thought I put some comments into it
So normally, if a user, for example, evaluates [1,2,3,4] you'd expect the following output:
After monkeypatching InjectedScript._evaluateAndWrap evaluating the very same expression, gives the following output:
As you see the little-left arrow, indicating output, is still there, but this time we get an object. Where the result of the expression, the array [1,2,3,4] is represented as an object with all its properties described.
I recommend trying to evaluate this and that expression, including those that generate errors. It's quite interesting.
Additionally, take a look at the is - InjectedScriptHost - object. It provides some methods to play with and get a bit of insight into the internals of the inspector.
Of course, you could intercept all that information and still return the original result to the user.
Just replace the return statement in the else path by a console.log (res) following a return res. Then you'd end up with the following.
End of Edit
This is the prior version which was fixed by Google. Hence not a possible way anymore.
One of it is hooking into Function.prototype.call
Chrome evaluates the entered expression by calling its eval function with InjectedScriptHost as thisArg
var result = evalFunction.call(object, expression);
Given this, you can listen for the thisArg of call being evaluate and get a reference to the first argument (InjectedScriptHost)
if (window.URL) {
var ish, _call = Function.prototype.call;
Function.prototype.call = function () { //Could be wrapped in a setter for _commandLineAPI, to redefine only when the user started typing.
if (arguments.length > 0 && this.name === "evaluate" && arguments [0].constructor.name === "InjectedScriptHost") { //If thisArg is the evaluate function and the arg0 is the ISH
ish = arguments[0];
ish.evaluate = function (e) { //Redefine the evaluation behaviour
throw new Error ('Rejected evaluation of: \n\'' + e.split ('\n').slice(1,-1).join ("\n") + '\'');
};
Function.prototype.call = _call; //Reset the Function.prototype.call
return _call.apply(this, arguments);
}
};
}
You could e.g. throw an error, that the evaluation was rejected.
Here is an example where the entered expression gets passed to a CoffeeScript compiler before passing it to the evaluate function.
Netflix also implements this feature
(function() {
try {
var $_console$$ = console;
Object.defineProperty(window, "console", {
get: function() {
if ($_console$$._commandLineAPI)
throw "Sorry, for security reasons, the script console is deactivated on netflix.com";
return $_console$$
},
set: function($val$$) {
$_console$$ = $val$$
}
})
} catch ($ignore$$) {
}
})();
They just override console._commandLineAPI to throw security error.
This is actually possible since Facebook was able to do it.
Well, not the actual web developer tools but the execution of Javascript in console.
See this: How does Facebook disable the browser's integrated Developer Tools?
This really wont do much though since there are other ways to bypass this type of client-side security.
When you say it is client-side, it happens outside the control of the server, so there is not much you can do about it. If you are asking why Facebook still does this, this is not really for security but to protect normal users that do not know javascript from running code (that they don't know how to read) into the console. This is common for sites that promise auto-liker service or other Facebook functionality bots after you do what they ask you to do, where in most cases, they give you a snip of javascript to run in console.
If you don't have as much users as Facebook, then I don't think there's any need to do what Facebook is doing.
Even if you disable Javascript in console, running javascript via address bar is still possible.
and if the browser disables javascript at address bar, (When you paste code to the address bar in Google Chrome, it deletes the phrase 'javascript:') pasting javascript into one of the links via inspect element is still possible.
Inspect the anchor:
Paste code in href:
Bottom line is server-side validation and security should be first, then do client-side after.
Chrome changed a lot since the times facebook could disable console...
As per March 2017 this doesn't work anymore.
Best you can do is disable some of the console functions, example:
if(!window.console) window.console = {};
var methods = ["log", "debug", "warn", "info", "dir", "dirxml", "trace", "profile"];
for(var i=0;i<methods.length;i++){
console[methods[i]] = function(){};
}
My simple way, but it can help for further variations on this subject.
List all methods and alter them to useless.
Object.getOwnPropertyNames(console).filter(function(property) {
return typeof console[property] == 'function';
}).forEach(function (verb) {
console[verb] =function(){return 'Sorry, for security reasons...';};
});
However, a better approach is to disable the developer tool from being opened in any meaningful way
(function() {
'use strict';
Object.getOwnPropertyNames(console).filter(function(property) {
return typeof console[property] == 'function';
}).forEach(function (verb) {
console[verb] =function(){return 'Sorry, for security reasons...';};
});
window.addEventListener('devtools-opened', ()=>{
// do some extra code if needed or ...
// maybe even delete the page, I still like to add redirect just in case
window.location.href+="#";
window.document.head.innerHTML="";
window.document.body.innerHTML="devtools, page is now cleared";
});
window.addEventListener('devtools-closed', ()=>{
// do some extra code if needed
});
let verifyConsole = () => {
var before = new Date().getTime();
debugger;
var after = new Date().getTime();
if (after - before > 100) { // user had to resume the script manually via opened dev tools
window.dispatchEvent(new Event('devtools-opened'));
}else{
window.dispatchEvent(new Event('devtools-closed'));
}
setTimeout(verifyConsole, 100);
}
verifyConsole();
})();
Internally devtools injects an IIFE named getCompletions into the page, called when a key is pressed inside the Devtools console.
Looking at the source of that function, it uses a few global functions which can be overwritten.
By using the Error constructor it's possible to get the call stack, which will include getCompletions when called by Devtools.
Example:
const disableDevtools = callback => {
const original = Object.getPrototypeOf;
Object.getPrototypeOf = (...args) => {
if (Error().stack.includes("getCompletions")) callback();
return original(...args);
};
};
disableDevtools(() => {
console.error("devtools has been disabled");
while (1);
});
an simple solution!
setInterval(()=>console.clear(),1500);
I have a simple way here:
window.console = function () {}
I would go along the way of:
Object.defineProperty(window, 'console', {
get: function() {
},
set: function() {
}
});
In Firefox it dosen't do that, since Firefox is a developer browser, I think since the command WEBGL_debug_renderer_info is deprecated in Firefox and will be removed. Please use RENDERER and the error Referrer Policy: Less restricted policies, including ‘no-referrer-when-downgrade’, ‘origin-when-cross-origin’ and ‘unsafe-url’, will be ignored soon for the cross-site request: https://static.xx.fbcdn.net/rsrc.php/v3/yS/r/XDDAHSZfaR6.js?_nc_x=Ij3Wp8lg5Kz.
This is not a security measure for weak code to be left unattended. Always get a permanent solution to weak code and secure your websites properly before implementing this strategy
The best tool by far according to my knowledge would be to add multiple javascript files that simply changes the integrity of the page back to normal by refreshing or replacing content. Disabling this developer tool would not be the greatest idea since bypassing is always in question since the code is part of the browser and not a server rendering, thus it could be cracked.
Should you have js file one checking for <element> changes on important elements and js file two and js file three checking that this file exists per period you will have full integrity restore on the page within the period.
Lets take an example of the 4 files and show you what I mean.
index.html
<!DOCTYPE html>
<html>
<head id="mainhead">
<script src="ks.js" id="ksjs"></script>
<script src="mainfile.js" id="mainjs"></script>
<link rel="stylesheet" href="style.css" id="style">
<meta id="meta1" name="description" content="Proper mitigation against script kiddies via Javascript" >
</head>
<body>
<h1 id="heading" name="dontdel" value="2">Delete this from console and it will refresh. If you change the name attribute in this it will also refresh. This is mitigating an attack on attribute change via console to exploit vulnerabilities. You can even try and change the value attribute from 2 to anything you like. If This script says it is 2 it should be 2 or it will refresh. </h1>
<h3>Deleting this wont refresh the page due to it having no integrity check on it</h3>
<p>You can also add this type of error checking on meta tags and add one script out of the head tag to check for changes in the head tag. You can add many js files to ensure an attacker cannot delete all in the second it takes to refresh. Be creative and make this your own as your website needs it.
</p>
<p>This is not the end of it since we can still enter any tag to load anything from everywhere (Dependent on headers etc) but we want to prevent the important ones like an override in meta tags that load headers. The console is designed to edit html but that could add potential html that is dangerous. You should not be able to enter any meta tags into this document unless it is as specified by the ks.js file as permissable. <br>This is not only possible with meta tags but you can do this for important tags like input and script. This is not a replacement for headers!!! Add your headers aswell and protect them with this method.</p>
</body>
<script src="ps.js" id="psjs"></script>
</html>
mainfile.js
setInterval(function() {
// check for existence of other scripts. This part will go in all other files to check for this file aswell.
var ksExists = document.getElementById("ksjs");
if(ksExists) {
}else{ location.reload();};
var psExists = document.getElementById("psjs");
if(psExists) {
}else{ location.reload();};
var styleExists = document.getElementById("style");
if(styleExists) {
}else{ location.reload();};
}, 1 * 1000); // 1 * 1000 milsec
ps.js
/*This script checks if mainjs exists as an element. If main js is not existent as an id in the html file reload!You can add this to all js files to ensure that your page integrity is perfect every second. If the page integrity is bad it reloads the page automatically and the process is restarted. This will blind an attacker as he has one second to disable every javascript file in your system which is impossible.
*/
setInterval(function() {
// check for existence of other scripts. This part will go in all other files to check for this file aswell.
var mainExists = document.getElementById("mainjs");
if(mainExists) {
}else{ location.reload();};
//check that heading with id exists and name tag is dontdel.
var headingExists = document.getElementById("heading");
if(headingExists) {
}else{ location.reload();};
var integrityHeading = headingExists.getAttribute('name');
if(integrityHeading == 'dontdel') {
}else{ location.reload();};
var integrity2Heading = headingExists.getAttribute('value');
if(integrity2Heading == '2') {
}else{ location.reload();};
//check that all meta tags stay there
var meta1Exists = document.getElementById("meta1");
if(meta1Exists) {
}else{ location.reload();};
var headExists = document.getElementById("mainhead");
if(headExists) {
}else{ location.reload();};
}, 1 * 1000); // 1 * 1000 milsec
ks.js
/*This script checks if mainjs exists as an element. If main js is not existent as an id in the html file reload! You can add this to all js files to ensure that your page integrity is perfect every second. If the page integrity is bad it reloads the page automatically and the process is restarted. This will blind an attacker as he has one second to disable every javascript file in your system which is impossible.
*/
setInterval(function() {
// check for existence of other scripts. This part will go in all other files to check for this file aswell.
var mainExists = document.getElementById("mainjs");
if(mainExists) {
}else{ location.reload();};
//Check meta tag 1 for content changes. meta1 will always be 0. This you do for each meta on the page to ensure content credibility. No one will change a meta and get away with it. Addition of a meta in spot 10, say a meta after the id="meta10" should also be covered as below.
var x = document.getElementsByTagName("meta")[0];
var p = x.getAttribute("name");
var s = x.getAttribute("content");
if (p != 'description') {
location.reload();
}
if ( s != 'Proper mitigation against script kiddies via Javascript') {
location.reload();
}
// This will prevent a meta tag after this meta tag # id="meta1". This prevents new meta tags from being added to your pages. This can be used for scripts or any tag you feel is needed to do integrity check on like inputs and scripts. (Yet again. It is not a replacement for headers to be added. Add your headers aswell!)
var lastMeta = document.getElementsByTagName("meta")[1];
if (lastMeta) {
location.reload();
}
}, 1 * 1000); // 1 * 1000 milsec
style.css
Now this is just to show it works on all files and tags aswell
#heading {
background-color:red;
}
If you put all these files together and build the example you will see the function of this measure. This will prevent some unforseen injections should you implement it correctly on all important elements in your index file especially when working with PHP.
Why I chose reload instead of change back to normal value per attribute is the fact that some attackers could have another part of the website already configured and ready and it lessens code amount. The reload will remove all the attacker's hard work and he will probably go play somewhere easier.
Another note: This could become a lot of code so keep it clean and make sure to add definitions to where they belong to make edits easy in future. Also set the seconds to your preferred amount as 1 second intervals on large pages could have drastic effects on older computers your visitors might be using
I have this tiny little script that I run inside Chrome using Tampermonkey and works great.
However, when I use it in Firefox with Greasemonkey, it shows up on the active list, meaning its matching the page but it doesn't actually execute the code. I know it has to be a simple something I am overlooking but its not hitting me.
var myVar=setInterval(function(){myTimer();},100);
function myStopFunction()
{
clearInterval(myVar);
}
function myTimer()
{
var p1 = "Login";
var p2 = "mode=login";
var x = document.body.innerHTML;
if (x.match(p1) && x.match(p2)){
document.documentURI = "/ucp.php?mode=login";
}
myStopFunction();
}
Script Logic/Function
I am using a timer to prevent the script from triggering over and over in a permanent loop.
It simply detects if I am logged into a phpBB forum or not, if not send me to the login page so I can log in.
I am using document URI so that the location of the original is preserved so upon login, it takes me right back to it.
Often phpBB when you log in, it will take you back to the index page so this preserves my original intent of going to the actual link.
This script works perfectly and as expected on Chrome using TM but on Firefox using GM it doesn't trigger, am I missing something here?
From the Firefox spec:
(document.documentURI)
Returns the document location as string. It is read-only per DOM4 specification.
And, indeed, the latest spec still specifies that this attribute must be read only.
If Chrome lets you write this property, then that is non-standard behavior and maybe a bug.
Use location.assign(), or location.replace(), or just programmatically click the login button -- which often preserves the target page.
I thought I'd found the solution a while ago (see my blog):
If you ever get the JavaScript (or should that be JScript) error "Can't execute code from a freed script" - try moving any meta tags in the head so that they're before your script tags.
...but based on one of the most recent blog comments, the fix I suggested may not work for everyone. I thought this would be a good one to open up to the StackOverflow community....
What causes the error "Can't execute code from a freed script" and what are the solutions/workarounds?
You get this error when you call a function that was created in a window or frame that no longer exists.
If you don't know in advance if the window still exists, you can do a try/catch to detect it:
try
{
f();
}
catch(e)
{
if (e.number == -2146823277)
// f is no longer available
...
}
The error is caused when the 'parent' window of script is disposed (ie: closed) but a reference to the script which is still held (such as in another window) is invoked. Even though the 'object' is still alive, the context in which it wants to execute is not.
It's somewhat dirty, but it works for my Windows Sidebar Gadget:
Here is the general idea:
The 'main' window sets up a function which will eval'uate some code, yup, it's that ugly.
Then a 'child' can call this "builder function" (which is /bound to the scope of the main window/) and get back a function which is also bound to the 'main' window. An obvious disadvantage is, of course, that the function being 'rebound' can't closure over the scope it is seemingly defined in... anyway, enough of the gibbering:
This is partially pseudo-code, but I use a variant of it on a Windows Sidebar Gadget (I keep saying this because Sidebar Gadgets run in "unrestricted zone 0", which may -- or may not -- change the scenario greatly.)
// This has to be setup from the main window, not a child/etc!
mainWindow.functionBuilder = function (func, args) {
// trim the name, if any
var funcStr = ("" + func).replace(/^function\s+[^\s(]+\s*\(/, "function (")
try {
var rebuilt
eval("rebuilt = (" + funcStr + ")")
return rebuilt(args)
} catch (e) {
alert("oops! " + e.message)
}
}
// then in the child, as an example
// as stated above, even though function (args) looks like it's
// a closure in the child scope, IT IS NOT. There you go :)
var x = {blerg: 2}
functionInMainWindowContenxt = mainWindow.functionBuilder(function (args) {
// in here args is in the bound scope -- have at the child objects! :-/
function fn (blah) {
return blah * args.blerg
}
return fn
}, x)
x.blerg = 7
functionInMainWindowContext(6) // -> 42 if I did my math right
As a variant, the main window should be able to pass the functionBuilder function to the child window -- as long as the functionBuilder function is defined in the main window context!
I feel like I used too many words. YMMV.
Here's a very specific case in which I've seen this behavior. It is reproducible for me in IE6 and IE7.
From within an iframe:
window.parent.mySpecialHandler = function() { ...work... }
Then, after reloading the iframe with new content, in the window containing the iframe:
window.mySpecialHandler();
This call fails with "Can't execute code from a freed script" because mySpecialHandler was defined in a context (the iframe's original DOM) that no longer exits. (Reloading the iframe destroyed this context.)
You can however safely set "serializeable" values (primitives, object graphs that don't reference functions directly) in the parent window. If you really need a separate window (in my case, an iframe) to specify some work to a remote window, you can pass the work as a String and "eval" it in the receiver. Be careful with this, it generally doesn't make for a clean or secure implementation.
If you are trying to access the JS object, the easiest way is to create a copy:
var objectCopy = JSON.parse(JSON.stringify(object));
Hope it'll help.
This error can occur in MSIE when a child window tries to communicate with a parent window which is no longer open.
(Not exactly the most helpful error message text in the world.)
Beginning in IE9 we began receiving this error when calling .getTime() on a Date object stored in an Array within another Object. The solution was to make sure it was a Date before calling Date methods:
Fail: rowTime = wl.rowData[a][12].getTime()
Pass: rowTime = new Date(wl.rowData[a][12]).getTime()
I ran into this problem when inside of a child frame I added a reference type to the top level window and attempted to access it after the child window reloaded
i.e.
// set the value on first load
window.top.timestamp = new Date();
// after frame reloads, try to access the value
if(window.top.timestamp) // <--- Raises exception
...
I was able to resolve the issue by using only primitive types
// set the value on first load
window.top.timestamp = Number(new Date());
This isn't really an answer, but more an example of where this precisely happens.
We have frame A and frame B (this wasn't my idea, but I have to live with it). Frame A never changes, Frame B changes constantly. We cannot apply code changes directly into frame A, so (per the vendor's instructions) we can only run JavaScript in frame B - the exact frame that keeps changing.
We have a piece of JavaScript that needs to run every 5 seconds, so the JavaScript in frame B create a new script tag and inserts into into the head section of frame B. The setInterval exists in this new scripts (the one injected), as well as the function to invoke. Even though the injected JavaScript is technically loaded by frame A (since it now contains the script tag), once frame B changes, the function is no longer accessible by the setInterval.
I got this error in IE9 within a page that eventually opens an iFrame. As long as the iFrame wasn't open, I could use localStorage. Once the iFrame was opened and closed, I wasn't able to use the localStorage anymore because of this error. To fix it, I had to add this code to in the Javascript that was inside the iFrame and also using the localStorage.
if (window.parent) {
localStorage = window.parent.localStorage;
}
got this error in DHTMLX while opening a dialogue & parent id or current window id not found
$(document).ready(function () {
if (parent.dxWindowMngr == undefined) return;
DhtmlxJS.GetCurrentWindow('wnManageConDlg').show();
});
Just make sure you are sending correct curr/parent window id while opening a dialogue
On update of iframe's src i am getting that error.
Got that error by accessing an event(click in my case) of an element in the main window like this (calling the main/outmost window directly):
top.$("#settings").on("click",function(){
$("#settings_modal").modal("show");
});
I just changed it like this and it works fine (calling the parent of the parent of the iframe window):
$('#settings', window.parent.parent.document).on("click",function(){
$("#settings_modal").modal("show");
});
My iframe containing the modal is also inside another iframe.
The explanations are very relevant in the previous answers. Just trying to provide my scenario. Hope this can help others.
we were using:
<script> window.document.writeln(table) </script>
, and calling other functions in the script on onchange events but writeln completely overrides the HTML in IE where as it is having different behavior in chrome.
we changed it to:
<script> window.document.body.innerHTML = table;</script>
Thus retained the script which fixed the issue.