When we visit a website, we do several things like click on text, images and hyperlinks etc. These are examples of what JavaScript calls events.
We can write our event handlers in JavaScript or VBScript and can specify these event handlers as a value of event tag attribute.
In XHTML Event handler, we can associate event handlers to a tag by specifying attributes. These attributes are onload, onclick, onsubmit etc can be apply to the form and button tags.
The <body> and <frameset> Level Events
In <body> and <frameset> level events, two attributes are used to trigger any JavaScript or VBScript code, when any event occurs at document level.
| Attribute |
Value |
Description |
| Onload |
Event handler |
It calls event handler when a XHTML document loads. |
| Onunload |
Event handler |
It calls event handler when a XHTML document unloads. |
Note: Here, The Event handler refers to any function or piece of Event handler of VBScript or JavaScript.
The <form> Level Events
In <form> level Events, six attributes are used to trigger any JavaScript or VBScript code when any event occurs at form level.
| Attribute |
Value |
Description |
| Onchange |
Event handler |
Event handler executes when the element Changes. |
| Onsubmit |
Event handler |
Event handler executes when the form is submitted. |
| Onreset |
Event handler |
Event handler executes when the form is reset. |
| Onselect |
Event handler |
Event handler executes when the element is selected. |
| Onblur |
Event handler |
Event handler executes when the element loses focus. |
| Onfocus |
Event handler |
Event handler runs when the element gets focus. |
Keyboard Events
In Keyboard Events, three events are generated.
Keyboard events are not valid in base, bdo, br, frameset, frame, head, html, meta, iframe, param, script, style, and title elements.
| Attribute |
Value |
Description |
| Onkeydown |
Event handler |
Event handler executes on key press. |
| Onkeypress |
Event handler |
Event handler executes on key press and release. |
| Onkeyup |
Event handler |
Event handler executes on key release. |
Mouse Events
In Mouse Events, seven events are generated.
Mouse events are not valid in base, bdo, br, frameset, frame, head, html, meta, iframe, param, script, style, and title elements.
| Attribute |
Value |
Description |
| Onclick |
Event handler |
Event handler executes on a mouse click. |
| Ondblclick |
Event handler |
Event handler executes on a mouse-double click. |
| Onmousedown |
Event handler |
Event handler executes when a mouse button is pressed. |
| Onmousemove |
Event handler |
Event handler executes when mouse pointer is moved. |
| Onmouseout |
Event handler |
Event handler executes when mouse pointer moves out of an element. |
| Onmouseover |
Event handler |
Event handler executes when mouse pointer moves over an element. |
| Onmouseup |
Event handler |
Event handler executes when mouse button is released. |