This question already has answers here:
How to make the HTML renders before the alert is triggered?
(4 answers)
placing <script> tags right before </body> doesn't work as expected
(3 answers)
Closed 1 year ago.
My javascript is running before my HTML loads, even if I put it right before the like this:
<body>
<h1>Title</h1>
<script>
alert("yo");
</script>
</body>
Any ideas why that may be happening?
Any ideas why that may be happening?
alert is blocking, script evaluation comes before DomContentLoaded (DCL) and subsequent first content paint (FCP) which is why it doesn't show Title before alert starts blocking the dom.
You could run it this way:
<body onload="alert('yo')">
<h1>Title</h1>
</body>
Or this way:
<body onload="my_function()">
<h1>Title</h1>
<script>
function my_function() {
alert('yo');
}
</script>
</body>
Related
This question already has answers here:
Why can't I call a function named clear from an onclick attribute?
(3 answers)
Closed 9 months ago.
htmlfile:
<!DOCTYPE html>
<head>
<script src="script.js"></script>
</head>
<body>
<div class="q" id="cooki" onclick="cookie()">Accept!</div>
</body>
js:
function cookie() {
alert("hi");
}
and I even tested with console.log, I used script source in body tags , nothing worked
Hi #Z3N1X Welcome to Stackoverflow.
To fix your issue try renaming your function to something else,
since how all of the comments below the answer has said(Thanks for correcting me)
when you use the cookie name in the function or variable the onclick thinks your trying to use the document.cookie function.
that's why this is happening.
This question already has answers here:
Why does jQuery or a DOM method such as getElementById not find the element?
(6 answers)
Closed 6 years ago.
I am very new to jQuery, literally just trying to get it to work for the first time. Only the alert box works, but none of the other very simple methods I am trying out. Here are the files:
HTML:
<!DOCTYPE HTML>
<html>
<head>
<title>jquery</title>
<script type="text/javascript" src="jquery-3.1.0.min.js"></script>
<script type="text/javascript" src="myJavaScript.js"></script>
</head>
<body>
<h1 id="title">This is a title</h1>
<p> This is some sample text.</p>
</body>
</html>
JavaScript file:
$(document).ready(function (){alert("this works!")});
$("#title").text("but this is not not working");
As you can see the example can't be simpler. I have off course downloaded the jquery-3.1.0.min.js file and put it in the same folder as the html. If I comment out the link, the alert stops working, so I now the file is being referenced OK. Why is the second line of jQuery not working? Many thanks, P
Because the DOM(the entire structure of your application) isn't loaded yet. You need to use a $(document).ready(makes sure the DOM is loaded before running jQuery code) or an event handler to make the change visible.
This question already has answers here:
Why does jQuery or a DOM method such as getElementById not find the element?
(6 answers)
Closed 6 years ago.
I don't understand why this simple script works only when I place it in the body?
when i place the script within the head or in external JS file it doesn't work.
<!DOCTYPE html>
<html>
<body>
<h1>My First Web Page</h1>
<p>My First Paragraph</p>
<p id="demo"></p>
<script>
document.getElementById("demo").innerHTML = 5 + 6;
</script>
</body>
</html>
Because the element you reference is defined only later (at the time the <head> is processed the browser hasn't processed the markup underneath it yet).
This question already has answers here:
JavaScript getElementByID() not working [duplicate]
(3 answers)
Closed 7 years ago.
The Problem
I'm trying to display the output of a function to a div, but i can't figure out why it isn't displaying. How can i fix this so that it displays properly?
What i've tried so far
I've copied a document.getElementById statement from another codeblock i wrote that is functioning , and checked it for any typos etc. All seems well there.
I googled innerHTML to be sure that I was using it correctly.
Also changed the document.etc line to document.write to ensure the function was working properly, it output properly.
My Code
<html>
<head>
<script type="text/javascript">
function parameters(one, two) {
document.getElementById('output').innerHTML=(one + two);
}
parameters("coding" , "coffee");
</script>
</head>
<body>
<div id="output"></div>
</body>
</html>
The problem is that you're trying to use the div#output before it's even loaded by the browser.
There are two simple solutions for this:
First
Put the <script> tag after the div#output, so it will be already loaded.
<html>
<head>
</head>
<body>
<div id="output"></div>
<script type="text/javascript">
function parameters(one, two) {
document.getElementById('output').innerHTML=(one + two);
}
parameters("coding" , "coffee");
</script>
</body>
</html>
Second
Put your Javascript code inside the DOMContentLoaded event, so it will only be called after all the DOMElements are loaded in your page.
<html>
<head>
<script type="text/javascript">
function parameters(one, two) {
document.getElementById('output').innerHTML=(one + two);
}
document.addEventListener('DOMContentLoaded', function() {
parameters("coding" , "coffee");
});
</script>
</head>
<body>
<div id="output"></div>
</body>
</html>
This question already has answers here:
Why does jQuery or a DOM method such as getElementById not find the element?
(6 answers)
Closed 9 years ago.
I'm trying to get the element with getElementById(), but it returns null even though the element exists. What am I doing wrong?
<html>
<head>
<title>blah</title>
<script type="text/javascript">
alert(document.getElementById("abc"));
</script>
</head>
<body>
<div id="abc">
</div>
</body>
You have to put this in a document load event. The DOM hasn't gotten to abc by the time the script is executed.
Your script runs before the DOM has been loaded. To fix this you can place your code in the window.onload function like so:
window.onload = function() {
alert(document.getElementById("abc"));
};
An alternative is to place your script right before the closing </body> tag.
If you don't want to attach to the load event then simply put your script at the bottom of the body, so it will execute at the end-
<html>
<head>
<title>blah</title>
</head>
<body>
<div id="abc">
</div>
<script type="text/javascript">
alert(document.getElementById("abc"));
</script>
</body>
</html>
This is because the script runs before the page has rendered.
For proof add this attribute to the body tag:
<body onload="alert(document.getElementById('abc'));" >
But it doesn't exist, not at that point in the HTML. HTML documents are parsed top-to-bottom, just like programs run. The best solution is just to put your script tag at the bottom of the page. You could also attach your JavaScript to the onload event.