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Run Js function only once after 2 seconds from c# code behind

Hello i have the next question, ive got the next function =
protected void lnk_Click( object sender, EventArgs e )
{
LinkButton btn = sender as LinkButton;
string text = btn.CommandName;
ScriptManager.RegisterStartupScript( this, GetType(), "script", "alert('"+ text + "');", true );
}
I want to run the function after a second or 1.5 secs because this is running before the page renders visually, causing a "visual bug" on which the li tags (for example) dont get the css properties.
Any suggestion would help, thanks!

The JavaScript content should run on the event DOMContentLoaded like this:
document.addEventListener("DOMContentLoaded", function(){alert('text');});
If you're sure you want to use the "dirty" way, use setTimeout:
setTimeout(function(){alert('text');}, 1500); // 1500 milliseconds

In async you can wait using Task.Delay
private async Task<Response> ExecuteTask(Request request)
{
var response = await GetResponse();
switch(response.Status)
{
case ResponseStatus.Pending:
await Task.Delay(TimeSpan.FromSeconds(2))
response = await ExecuteTask(request);
break;
}
return response;
}

Pause loading script and resume after load element of DOM

I need the js script to stop and wait until a certain element appears on the page.
Can this be done with promises?
The fact is that the portal on which the script is used dynamically loads pages without going to the URL, and the necessary part of the script is to be executed on a specific page

Instead of stoping execution, you can move the code into into its own function and execute only after the element appears in DOM.
var check = setInterval("checkElem", 200);
function checkClear() {
clearInterval(check);
}
function checkElem() {
const el1 = document.getElementById("element1");
if (el1 !== null) {
console.log("executing");
yourFunction();
checkClear();
} else {
console.log("element does NOT exist");
}
}
function yourFunction() {
//your executable code
return "some-value";
}

How to prevent content script from having DOM injection race conditions?

I have a content script which modifies the DOM based on the current url.
My background script listens to chrome.webNavigation.onHistoryStateUpdated and sends a message to the content script with the current url:
chrome.webNavigation.onHistoryStateUpdated.addListener(onNavigation, { url: ... });
async function onNavigation(details) {
const { url, tabId } = details;
chrome.tabs.sendMessage(tabId, { id: 'my-msg-id', url });
}
Then, based on the url, the content script injects a certain div to the current page:
chrome.runtime.onMessage.addListener(async (message, sender, sendResponse) => {
if (message.id === 'my-msg-id' && message.url === '...') {
await injectDiv();
}
...
});
My problem is that sometimes, the same div gets injected to the DOM twice.
This looks like a race condition that happens:
When the page loads slowly.
When the user navigates quickly between urls or goes back and forth between pages.
What I've tried:
Wrapping the injection logic with a guard like this:
async function injectDiv() {
if (document.getElementById('my-div-id')) {
return;
}
const myDiv = document.createElement('div');
myDiv.id = 'my-div-id';
... // Some async code that waits until the container is loaded to the DOM using setInterval
const container = document.querySelector('div.container');
container.appendChild(myDiv);
}
Using throttle to limit the url triggers sent from the background script to the content script:
const throttledNav = throttle(onNavigation, 2000, { leading: true, trailing: true });
chrome.webNavigation.onHistoryStateUpdated.addListener(throttledNav, { url: ... });
It looks like it helped with most cases but I still get a double (or even a triple) duplicate DOM injection of my div from time to time, which makes my extension look very buggy.
What can I do to fix this?

Cordova InAppBowser not loading DOM of result of each page after executescript

All,
Am using cordova inappbrowser. I load the a page uisng window.open. Then hook to loadstop and execute a javascript . The result of execution is another web page. Now I want to manipulate the document elements in that page. So i hook to another laodstop event, but that is not getting my second page. Some docs show , executescript returns an array, but not sure where the html dom is contained.
<script>
var inAppBrowserRef;
function OpenSRMS() {
inAppBrowserRef = window.open('myink','_blank','location=no');
inAppBrowserRef.addEventListener('loadstop', loginSRMS);
}
function loginSRMS() {
if (inAppBrowserRef != undefined) {
inAppBrowserRef.executeScript({ code: "document.getElementById('userName').value = 'Training';" +
"document.getElementById('password').value = 'Training';" +
"document.getElementById(\"frm\").submit();"});
}
inAppBrowserRef.addEventListener('loadstop', INQCS);
}
function INQCS(){
if (inAppBrowserRef != undefined) {
inAppBrowserRef.executeScript({ code: "alert('hello');"});
}
}
</script>

How to wait for a Java applet to finish loading on Safari?

This doesn't work in Safari:
<html>
<body>
<applet id="MyApplet" code="MyAppletClass" archive="MyApplet.jar">
<script type="text/javascript">
alert(document.getElementById('MyApplet').myMethod);
</script>
</body>
</html>
myMethod is a public method declared in MyAppletClass.
When I first load the page in Safari, it shows the alert before the applet has finished loading (so the message box displays undefined) . If I refresh the page, the applet has already been loaded and the alert displays function myMethod() { [native code] }, as you'd expect.
Of course, this means that the applet methods are not available until it has loaded, but Safari isn't blocking the JavaScript from running. The same problem happens with <body onLoad>.
What I need is something like <body onAppletLoad="doSomething()">. How do I work around this issue?
PS: I'm not sure if it's relevant, but the JAR is signed.

I use a timer that resets and keeps checking a number of times before it gives up.
<script language="text/javascript" defer>
function performAppletCode(count) {
var applet = document.getElementById('MyApplet');
if (!applet.myMethod && count > 0) {
setTimeout( function() { performAppletCode( --count ); }, 2000 );
}
else if (applet.myMethod) {
// use the applet for something
}
else {
alert( 'applet failed to load' );
}
}
performAppletCode( 10 );
</script>
Note that this assumes that the applet will run in Safari. I've had some instances where an applet required Java 6 that simply hangs Safari even with code similar to the above. I chose to do browser detection on the server and redirect the user to an error page when the browser doesn't support the applet.

Here is a generic function I wrote to do just this:
/* Attempt to load the applet up to "X" times with a delay. If it succeeds, then execute the callback function. */
function WaitForAppletLoad(applet_id, attempts, delay, onSuccessCallback, onFailCallback) {
//Test
var to = typeof (document.getElementById(applet_id));
if (to == "function") {
onSuccessCallback(); //Go do it.
return true;
} else {
if (attempts == 0) {
onFailCallback();
return false;
} else {
//Put it back in the hopper.
setTimeout(function () {
WaitForAppletLoad(applet_id, --attempts, delay, onSuccessCallback, onFailCallback);
}, delay);
}
}
}
Call it like this:
WaitForAppletLoad("fileapplet", 10, 2000, function () {
document.getElementById("fileapplet").getDirectoriesObject("c:/");
}, function () {
alert("Sorry, unable to load the local file browser.");
});

I had a similar problem some time ago and adding MAYSCRIPT to the applet tag solved my problem.
Take a peek at this page:
http://www.htmlcodetutorial.com/applets/_APPLET_MAYSCRIPT.html
Hope it helps!