The HTML onerror event attribute is triggered when an error occurs while loading an external file in an HTML document.
Syntax
Following is the syntax −
<tagname onerror=”script”>Content</tagname>
Let us see an example of HTML onerror event Attribute −
Example
<!DOCTYPE html>
<html>
<head>
<style>
body {
color: #000;
height: 100vh;
background: linear-gradient(62deg, #FBAB7E 0%, #F7CE68 100%) no-repeat;
text-align: center;
padding: 20px;
}
.btn {
background: #db133a;
border: none;
height: 2rem;
border-radius: 2px;
width: 40%;
display: block;
color: #fff;
outline: none;
cursor: pointer;
margin: 1rem auto;
}
</style>
</head>
<body>
<h1>HTML onerror Event Attribute Demo</h1>
<button onclick="add()" class="btn">Add Nature Image</button>
<script>
function add() {
var imgEle = document.createElement('IMG');
imgEle.setAttribute("src", "nature.png");
imgEle.setAttribute("alt", "nature image");
imgEle.setAttribute("onerror", "errorFn()");
document.body.appendChild(imgEle);
}
function errorFn() {
document.body.style.background = "linear-gradient(45deg, #8BC6EC 0%, #9599E2 100%) no-repeat";
document.body.style.color = "#fff";
}
</script>
</body>
</html>Output

Click on “Add Nature Image” button to create an image element with wrong source attribute and with onerror event attribute and then it to body element.
