HTML | ononline Event Attribute Last Updated : 16 Aug, 2022 Comments Improve Suggest changes Like Article Like Report The ononline event attribute works when the browser starts working in online mode. it is opposite to onoffline event attribute.Supported Tags <body> syntax <element ononline = "script"> Attribute Value: This event attribute contains single value script which works when browser working in online mode.Example: html <!DOCTYPE HTML> <html> <head> <title> ononline Event Attribute </title> <script> function onfunction() { alert("Browser is online"); } function offunction() { alert("browser is offline"); } </script> </head> <!-- ononline event used here --> <body ononline = "onfunction()" onoffline = "offunction()"> </body> </html> Output: Supported Browser: Chrome 3Edge 12Firefox 9Internet Explorer 9Opera 15Safar 4 Comment More infoAdvertise with us Next Article HTML onpageshow Event Attribute P PERIYANAYAKI Follow Improve Article Tags : HTML Technical Scripter 2018 Similar Reads HTML Event Attributes Reference HTML event attributes are used to define actions that should occur when specific events are triggered on a webpage.They enable interaction between the user and the system, like clicking a button or resizing a window.Event attributes are added to HTML elements to specify the event type and action.The 5 min read Window EventHTML onafterprint Event AttributeThe HTML onafterprint Event Attribute works when a page has started printing, or if the print dialogue box has been closed. This attribute is used together with the onbeforeprint attribute. This attribute is typically associated with the window or document element and is part of the WindowEventHandl 2 min read HTML onbeforeprint Event AttributeThe onbeforeprint event fires when a page is about to be printed before the print dialog box appears. This event can be used to perform actions before printing, such as hiding unnecessary elements or preparing the page for printing.Syntax: <element onbeforeprint = "script">Supported Tags:<b 2 min read HTML onbeforeunload Event AttributeThe onbeforeunload event runs when the document is about to be unloaded, thus, allowing to display message in a dialog box to inform the user whether a user wants to stay or leave the current page, i.e., this event triggers just before a user leaves a webpage, and helps to prevent an accidental clos 1 min read HTML onerror Event AttributeThe onerror event works when an error occurs while loading an external file. The external file may contain a document file or an image file. It simply activates when an error occurs during the loading of an external resource and It is commonly used to handle issues with image loading, script executi 2 min read HTML onhashchange Event AttributeHTML onhashchange Event Attribute works when there have been changes to the anchor part. The anchor part starts with the '#' symbol of the current URL. It also enables the execution of a script or function on hash change and is used for dynamic web applications updating without full page reload. In 2 min read HTML onload Event AttributeThe onload event attribute works when an object has been loaded. This attribute is mostly used within the <body> element to execute a script. It can be used with other elements as well. This attribute is used to check the visitor's browser type and browser version and load the proper version o 2 min read HTML onoffline Event AttributeThe onoffline event attribute works when the browser works in offline mode. It is the opposite of ononline event attribute. It is activated when the device loses its internet connection. It is also useful for adapting the web application's behavior when network connectivity is lost.Note: The `onoffl 1 min read HTML | ononline Event AttributeThe ononline event attribute works when the browser starts working in online mode. it is opposite to onoffline event attribute.Supported Tags <body> syntax <element ononline = "script"> Attribute Value: This event attribute contains single value script which works when browser working in 1 min read HTML onpageshow Event AttributeThe onpageshow event occurs when a user navigates to a website. This event is quite similar to onload event but it occurs after the onload event. It occurs every time, when the page is loaded whereas the onload event does not occur when the page is loaded from the cache. When a page is loaded or res 2 min read HTML onresize Event AttributeThe onresize event attribute is triggered each time when resizing the browser window size. It is generally used for responsive design, dynamically adjusting content layout during window resizing.To obtain the dimensions of an element, use the clientWidth, clientHeight, innerWidth, outerWidth, outerH 2 min read HTML onunload Event AttributeThe onunload event attribute works when the document is being unloaded i.e. it occurs when the browser has been closed. It is mostly used when the user opens a link and submits the form and closes the browser window. Basically, it is: Fired when a user navigates away from a page or closes the browse 1 min read Form EventHTML onblur AttributeThis attribute fires at that moment when the element loses focus. This attribute is mostly used in the Form validation code. This attribute is the opposite of onfocus attribute.Supported Tags: It supports all HTML elements except these elements which are given below : <base> <bdo> <br 2 min read HTML onchange Event AttributeThe onchange event attribute works when the value of the element changes and select the new value from the List. It is a part of the event attribute. It is similar to oninput event attribute. But the difference is that oninput attribute event occurs immediately after the value of the element changes 2 min read HTML | oncontextmenu Event AttributeThis attribute works when the user right-clicks on an element to open the context menu.Supported Tags: It supports all HTML elements. Syntax: <element oncontextmenu="script"> Attribute Value: This attribute contains single value script. The script to be run when oncontextmenu attribute called. 1 min read HTML onfocus Event AttributeThis onfocus attribute works when the element gets focused. This event attribute is mostly used with <input>, <select>, <a> elements. Supported Tags: It supports all HTML elements which are given below: <base> <bdo> <br> <head> <html> <iframe> 1 min read HTML oninput Event AttributeThis attribute works when it gets user input value. This attribute mainly fires when the user change the value of <input> and <textarea> element. This attribute is quite similar to onchange attribute but the basic difference is that the oninput event attribute occurs immediately when the 1 min read HTML oninvalid Event AttributeThe oninvalid event attribute works when input field values are invalid or empty. The script runs when a user clicks on the submit button. The required input field must be filled out before submitting it. It is basically triggered when a form element encounters invalid input and provides real-time f 2 min read HTML onreset Event AttributeThe onreset event attribute in HTML is triggered when reset the form. This Attribute works with form tag and is triggered when a form is reset, either by user action or programmatically. It also allows the execution of scripts or functions to handle actions after form reset. Syntax:<form onreset 2 min read HTML onsearch Event AttributeThis onsearch attribute works when a user presses the ENTER button or clicks on the x button. This event works with <input> element. Supported Tags: <input type="search">Syntax: <element onsearch="script">Attribute: This event contains single attribute script which contains the scr 1 min read HTML onselect Event AttributeThe onselect event attribute works when some text has been selected in an element. It is the part of event attribute. It is basically activated when text within an input or textarea is selected and enhances user interaction by responding to text highlighting. Syntax: <element onselect = "script" 2 min read HTML onsubmit Event AttributeThe onsubmit event attribute in HTML is triggered when a form is submitted. It is basically triggered when a form is submitted, either by clicking a submit button or using JavaScript. It is also useful for validating form data or performing actions before any submission and ensures better control an 2 min read Keyboard EventHTML onkeydown Event AttributeThe onkeydown event attribute works when the user presses any key from the keyboard. The onkeydown event is triggered when the down key is pressed down and used for capturing and responding to key events. Syntax: <element onkeydown = "script">Supported Tags: It supports all HTML elements EXCEP 2 min read HTML onkeypress AttributeThis attribute fires when a user presses a key on the Keyboard. This event attribute can not be used for all keys (e.g. ALT, CTRL, SHIFT, ESC) in all browsers.Supported Tags: All HTML elements, EXCEPT:<base><bdo><br><head><html><iframe><meta><param> 2 min read HTML onkeyup Event AttributeThe HTML onkeyup event attribute executes JavaScript code when a user releases a key after pressing it within an input field or textarea, enabling dynamic responses to keyboard input. It also enables real-time interaction with user input in web forms or applications and is commonly used for live sea 2 min read Mouse EventHTML onclick Event AttributeThe onclick event attribute in HTML triggers when the user clicks on an element. It executes a script or function upon a click event and is commonly used for interactive elements like buttons and links. Syntax<element onclick = "script">Attribute Value This attribute contains a single value sc 2 min read HTML ondblclick Event AttributeThe ondblclick Attribute Event occurs when a user fires the mouse Double click on Element. It is triggered when a user double-clicks on an HTML element and is used to initiate actions or functions in response to a double-click event. It also enables interactive features like opening pop-ups, display 2 min read HTML onmousedown AttributeThis onmousedown attribute will fire when a mouse button is pressed down on the element and the order of events occur related to the onmousedown event(for the left/mouse button) onmousedownonmouseuponclickSupported Tags: It supports all HTML elements. Syntax: <element onmousedown="script">Attr 2 min read HTML onmousemove Event AttributeThe HTML onmousemove event attribute triggers JavaScript code when the mouse pointer moves over an element, allowing interaction based on mouse movement within the webpage. Syntax: <element onmousemove = "script">Attribute Value: This attribute contains single value script which works when on 1 min read HTML onmouseout Event AttributeThe HTML  onmouseout event attribute works when the mouse pointer moves out of the specified element. It activates when the mouse pointer moves out of an HTML element. When a user moves the mouse away, this can be utilized to activate specific actions or functions and enables dynamic changes in resp 2 min read HTML onmouseover Event AttributeThe onmouseover event attribute works when the mouse pointer moves over the specified element. It is basically: Activated when the mouse pointer enters the designated HTML element.Enables executing JavaScript code when the mouse hovers over the element.Ideal for enhancing user experience by providin 2 min read HTML | onmouseup Event AttributeThis attribute fires when a mouse button is released over the element. The order of events occur related to the onmouseup event. onmousedownonmouseuponclick Supported Tags: All HTML elements, EXCEPT: <base> <bdo><br><head><html><iframe><meta><param> 1 min read HTML | onwheel Event AttributeThis attribute works when the wheel of pointer device is rolled up or down over an element. The onwheel attribute also works when the user scrolls or zooms on an element by using mouse or touchpad. Supported Tags: It supports all HTML elements. Syntax: <element onwheel = "script"> Attribute Va 1 min read Drag EventHTML ondrag Event AttributeThe ondrag event attribute triggers when the element or text selection is being dragged in HTML. This event is very similar to the drag-and-drop event. This will triggered during a drag operation when an HTML element is being dragged. Syntax<element ondrag = "script"> Supported TagsIt supports 1 min read HTML ondragend Event AttributeThe ondragend event attribute works when the user finishes the dragging of an element. The drag-and-drop feature is common in HTML5. Any element can be made draggable by using the HTML5 draggable attribute. It is fired when the user releases the mouse button or touch input also used for integrating 3 min read HTML ondragenter Event AttributeThe ondragenter Event attribute in HTML works when the content is draggable. An element is made by setting the draggable attribute value to true. The draggable attribute can take only true or false values and activates when a dragged element enters a valid drop target. Syntax<element ondragenter 2 min read HTML ondragleave Event AttributeThe ondragleave attribute works when a draggable element or text selection leaves a valid drop target. It helps in dragging the elements and get to know the entering or leaving a drop target. Drag and drop feature is very popular in HTML5. Use CSS property when the element is draggable and enter int 3 min read HTML ondragstart Event AttributeHTML ondragstart Event Attribute is used when the user wants to drag the text or element. It is simply the process in which we press on the desired text to drag and drop them to a different location. Basically, it Initiates when the user starts dragging an element and is used to set data to be trans 3 min read HTML ondrop Event AttributeThe ondrop event attribute is used to drag an element or text and drop it into a valid droppable location or target. The drag and drop is a common feature of HTML 5. There are different events that are used and occur before ondrop event. Events occur on the draggable targetEvents occur on the drop t 3 min read HTML onscroll AttributeThe onscroll attribute works when an element scrollbar is being scrolled. To create a scrollbar in an element, use the CSS overflow property. It is triggered when the content within an HTML element is scrolled and used to implement dynamic behaviors based on the scroll position and employed for crea 4 min read Clipboard EventsHTML oncopy AttributeThe oncopy Attribute attribute fires when the user copies the content present in an element. The oncopy attribute is used with <img>, <input>, <p> etc elements. It basically triggers on user-initiated copy operations and customizes behavior when content is copied.Syntax<element 2 min read HTML oncut AttributeThis attribute fires when the user cut or deletes the content that has been present in the element. It is a Boolean-type attribute. This attribute is supported by all HTML elements but it is possible for that element which has a ContentEditable attribute set to "true".Note:There are 3 ways to cut th 3 min read HTML onpaste Event AttributeThe onpaste attribute works when some content is pasted in an element. This event attribute is supported by all HTML elements. It is mostly used with <input> element.There are three ways to paste the content in HTML elements which are listed below: Use CTRL + V keySelect "Paste" from the edit 2 min read Misc EventsHTML ontoggle Event AttributeThe ontoggle event is triggered when the user opens or closes the <details> element. The <details> element is used to provide additional information/details that the user can view or hide details according to requirements. Syntax<details ontoggle = "script">Supported Tag<details 2 min read Like