Quiz Number 9

SWE 432, Fall 2009
November 5

  1. What does it mean for an Ajax request to be asynchronous?
    Answer: It means that the browser does not need to wait for the request to be serviced. (Any variant of an answer that gets to this notion is fine.)
  2. What new software must be installed on a browser or server to run applications that use Ajax?
    Answer: None. Ajax simply uses JavaScript, which is already on most browsers. (It is fine to note that some versions of some browers don't support Ajax.) Server code in any technology can be called. It is true that you need some server side support, but you really don't care what technology is used for that.
  3. Briefly explain the role of the XMLHttpRequest object in an Ajax transaction.
    Answer: This object is used as the communication vehicle between client and server in an Ajax transaction. The JavaScript function to be executed on return is bound to this object, arguments are transmitted through this object (either via GET or POST), and the response is obtained from this object. (Grading note: the notion that the object is the communication medium is the key.)