Navigator 3.0
<IMG SRC="url" onError="handler" a definition of the handler ...> image.onerror a reference to the handler image.onerror(); an explicit invocation of the handler
onerror() is an event handler invoked when an error occurs while the specified image is loading (for example, the network goes down, or the specified URL does not contain image data). This event handler is defined by the onError attribute of an <IMG> tag. The value of this attribute may be any number of JavaScript statements, separated by semicolons; these statements will be executed only when an error occurs while loading the specified image.