Window.onblur() Handler---invoked when window loses focus
Navigator 3.0
<BODY a definition of the handler [ onBlur="JavaScript statements" ] ... > <FRAMESET another way to define the handler [ onBlur="JavaScript statements" ] ... > window.onblur=handler-func defining the handler directly window.onblur(); an explicit invocation of the handler
onblur() is an event handler invoked by the browser when a top-level browser window loses the input focus, either because the user has switched to some other window, or because focus was explicitly transferred to another browser window with the Window blur() or focus() methods.
The onblur() event handler can be defined in HTML by specifying the onBlur attribute of the <BODY> or <FRAMESET> tag of the document or frameset that occupies the top-level window. The value of this attribute may be any number of JavaScript statements, separated by semicolons. This event handler may also be defined by assigning a function to the onblur property of the Window object.
If your web page does some sort of animation, you might use the onblur() event handler to stop the animation when the window doesn't have the input focus, on the theory that if the window doesn't have the focus, then the user probably can't see it or isn't paying attention to it.
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