Common JavaScript events: click, dblclick, mouseup, mouseout, keypress, keydown, keyup, error, load, resize, unload, blur, change, focus, reset, etc.
The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.
One of the basic features of JavaScript is event-driven. The so-called event-driven means that when the user performs a certain operation or the interaction between Javascript and html results in a certain state change, a series of program response executions will be triggered. Here, the user's operation is called an event, and the program's response to the event is called event processing.
Event processing refers to the program's response to events. For JavaScript, an event is an operation that occurs when a user interacts with a Web page or something that changes a certain state after the interaction between Javascript and HTML, such as moving the mouse, pressing a key, clicking a button, etc., and expressing Ajax The working status changes, indicating that the animation has completed running, etc. The program involved in event handling is called an event handler. Event handlers are usually defined as functions.
Interface elements that generate events in a Web page are called event sources. The same type of events can be generated on different event sources, and the same event source can also generate different types of events. The JS program specifies the event type and event source, and binds an event handler to the event source. In this way, once an event of a specified type occurs in the event source, the browser will call the handler bound to the event source for event processing. So the work involved in event processing includes the definition of event handlers and their binding.
In a Web page, there are many operations that users can perform, and each operation will generate an event. Let me introduce to you some common events in JavaScript.
Event | Description | |
---|---|---|
click | This event is triggered when the user clicks the mouse | |
This event is triggered when the user double-clicks the mouse | ||
This event is triggered when the user presses the mouse | ||
After the user presses the mouse This event is triggered when the mouse is released | ||
This event is triggered when the user moves the mouse cursor over an object range | ||
This event is triggered when the user moves the mouse | ||
This event is triggered when the user's mouse cursor leaves the scope of an object Event | ||
This event occurs when the mouse wheel is scrolled. It is only valid for IE and Chrome | ||
This event occurs when the mouse wheel is rolled, valid for standard browsers | ||
keypress | When the user presses the This event is triggered when a certain character key is pressed | |
This event is triggered when a key on the user's keyboard is pressed | ||
This event is triggered when a key on the user's keyboard is pressed and then released | ||
error | This event is triggered when an error occurs while loading a file or image | |
This event is triggered when the page content is loaded | ||
This event is triggered when the browser window size is changed | ||
When the current page is closed or exited Trigger this event | ||
blur | Trigger this event when the form element loses focus | |
This event is triggered when the user clicks the check box, radio button, normal button, submit button, reset button and other buttons | ||
This event is triggered when the content of the form element changes and the element loses focus | ||
This event is triggered when the form element gains focus | ||
This event is triggered when the user clicks the reset button on the form | ||
The user selects a This event is triggered when the text in the input or textarea form element | ||
This event is triggered when the user clicks the submit button to submit the form |
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