JavaScript HTML DOM events

Event

Event is a certain action performed by the user or the browser itself, such as click, load and mouseover are both event names.

Events are the bridge between javaScript and DOM.

If you trigger it, I will execute it - when the event occurs, its handler function is called to execute the corresponding JavaScript code to give a response.

Typical examples include: the load event is triggered when the page is loaded; the click event is triggered when the user clicks on an element.

Reacting to events

We can execute JavaScript when an event occurs, such as when the user clicks on an HTML element.

To execute code when the user clicks an element, add JavaScript code to an HTML event attribute:

onclick=JavaScript

HTML Examples of events:

When the user clicks the mouse

When the web page has loaded

When the image has loaded

When the mouse moves over the element

When the input field is changed

When the HTML form is submitted

When the user triggers a keypress

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To assign an event to an HTML element, you Event properties can be used.

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HTML DOM allows you to use JavaScript to assign events to HTML elements:

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##onload and onunload events

onload and onunload events Will be triggered when the user enters or leaves the page. The

onload event can be used to detect the visitor's browser type and browser version and load the correct version of the web page based on this information.

The onload and onunload events can be used to handle cookies.

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onchange event

The onchange event is often used in conjunction with validation of input fields.

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onmouseover and onmouseout events

The onmouseover and onmouseout events can be used to trigger functions when the user's mouse moves over or out of an HTML element.

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  Mouse Over Me

onmousedown, onmouseup and onclick events

onmousedown, onmouseup and onclick make up all parts of the mouse click event. First when the mouse button is clicked, the onmousedown event is fired, when the mouse button is released, the onmouseup event is fired, and finally, when the mouse click is completed, the onclick event is fired.