Occurs when the DownloadProgress (MediaElement) property has changed.
A token that is returned from the function, which you can optionally retain as a variable. If you intend to call RemoveEventListener to remove the handler, you will need this token.
The name of your event handler function as it is defined in script. When used as an AddEventListener parameter, quotation marks around the function name are not required. (See the "Remarks" section.)
Event Handler Parameters
The object that invoked the event.
This parameter is always set to null.
You can also add handlers in script by using a quoted string for the event handler name, as follows:
This syntax also returns a token. However, the token is not an absolute requirement for removing the handler in cases where the handler was added by using a quoted string. For details, see RemoveEventListener.
The DownloadProgressChanged event occurs for progressive downloads, typically occuring more than once. This event occurs whenever the amount of total content downloaded increases by 0.05 or more (as a factor of 1.0, which indicates completion), or reaches 1.0.