Requests a collection of either all text parts the current document contains or only the text part containing the input position from the server and returns the collection by calling a callback function which has to be provided as a parameter to the function.
A function with one parameter. Is called with an array of TextParts as a parameter containing the requested text parts as soon as the information has been retrieved from the server.
Optional. A boolean value indicating that only the text part containing the input position should be retrieved.