Client-side events are driven by the browser in response to end-user interaction with the page. You can create HTML Event Handlers that bind to HTML events and run client-side JavaScript when they are triggered.
To create these handlers click on the HTML Tab in the Custom Event Handlers area of the 
HTML Element Properties dialog.
Then select an event from the Event dropdown and launch the code editor by clicking ...
next to the code input.
Events include:
- onblur.
- onclick.
- onchange.
- ondblclick.
- onfocus.
- onkeydown.
- onkeypress.
- onkeyup.
- onmousedown.
- onmousemove.
- onmouseout.
- onmouseover.
- onmouseup.
- onresize.
- onselect.