JavaScript Events

By using JavaScript, we have the ability to create dynamic web pages. Events are actions that can be detected by JavaScript. Every element on a web page has certain events which can trigger JavaScript. For example, we can use the onClick event of a button element to indicate that a function will run when a user clicks on the button. We define the events in the HTML tags. Examples of events include: Events are normally used in combination with functions, and the function will not be executed before the event occurs! Below is a list of the attributes that can be inserted into HTML tags to define event actions where 
   FF: Firefox, N: Netscape, E: Edge
Attribute The Event Occurs When... FF N E
onabort Loading of an image is interrupted. 1 3 4
onblur An element loses focus. 1 2 3
onchange The user changes the content of a field. 1 2 3
onclick Mouse clicks an object. 1 2 3
ondblclick Mouse double-clicks an object. 1 4 4
onerror An error occurs when loading a document or an image. 1 3 4
onfocus An element gets focus. 1 2 3
onkeydown A keyboard key is pressed. 1 4 3
onkeypress A keyboard key is pressed or held down. 1 4 3
onkeyup A keyboard key is released. 1 4 3
onload A page or an image is finished loading. 1 2 3
onmousedown A mouse button is pressed. 1 4 4
onmousemove The mouse is moved. 1 6 3
onmouseout The mouse is moved off an element. 1 4 4
onmouseover The mouse is moved over an element. 1 2 3
onmouseup A mouse button is released. 1 4 4
onreset The reset button is clicked. 1 3 4
onresize A window or frame is resized. 1 4 4
onselect Text is selected. 1 2 3
onsubmit The submit button is clicked. 1 2 3
onunload The user exits the page. 1 2 3

Demonstration
The following demonstration shows how the script of HTML and JavaScript is displayed on the Web.

     





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