CS 101   Web Construction,  Summer 2006,  Instructor:  Jeffrey Horn

• Assignment 4  "Introduction to Dynamic Web Pages"

  • Handed out:  Tuesday, Oct. 2, 2007
  • Due:   Monday, Oct. 15, 2007
  • Purpose:
    1. Introduction to Javascript programming
    2. Learn to use basic prompts for user input
    3. Learn the use of the conditional statement ("if-then-else")
    4. Use a Boolean operator (equality:  "==")
  • Background:
    • http://www.dave-reed.com/book1ed/Chapter7/convert.html
    • Conditional execution (If-then-else statements):  see pp. 195-205 of Reed text.  Watch your {curly braces}! 
  • Details:
    • Create a web page that verifies that the user (viewer) is indeed a human (or at least, a VERY intelligent computer program!):
    • You have seen this before:  you are shown an image of some text, but the text is obscured by distortions, blurriness, and/or random-like patterns over the characters  .  You are asked to type into an input box the letters and numerals that  you see, then click "enter", "return", "submit", etc.  The purpose is to make it hard for any automated web crawler to get past this point, as it would require some sophisticated image-processing and character-recognition algorithms to see the actual characters in the image.  Heck, it takes ME some time to make sure I get it right!  (In my opinion, this task is just at the very edge of the current state of artificial intelligence research.)

      TASK 1:     CELSIUS->FAHRENHEIT

      • First, show me that you can work with Javascript.  Take the Temperature Conversion example from our text book (here) and change it so that it converts Celsius to Fahrenheit (instead of Fahrenheit to Celsius, which is what it does now).
      • Show me your code working.  (25 points)

      TASK 2:   HUMAN-DETECTOR

      • First show the user an image like the one above.  (10 pt.s)
      • Prompt the user for the text in the image (20 pt.s)
      • If the user gets it right, then show the user a special message.  (10 pt.s)
      • If the user gets it wrong, show them a different message.  (10 pt.s)
      • If the user gets it right, make the special message a mailto: (your email) (5 pt.s)
      • Make the mailto: as obscure as possible (10 pt.s)
      • Good style (indentation, comments, etc) in source code.  (10 pt.s)

       

  • Grading:  Total 100 pt.s.   The usual grading scale (i.e., 90 to 100 pt.s is an A, 80 to 89 pt.s is a B, etc.)
  • Turn-in Procedure:  Put your web pages on the web (use your myweb.nmu.edu web site or your own web server account if you have one).  Email me the URL for this assignment:  (jhorn@nmu.edu).  Keep it "secret"!  Use an obscure URL.