ITEC 325 2013spring ibarland

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hw02
hw02: A first php program

For this homework, make a folder itec325/hw02 on your H: drive. Inside this directory, you'll have two files for this assignment: utils.php that will contain php function definitions only, and utils-test.php that will contain test-cases.

• All files for this class (and for all your classes) must start with a comment containing: Your name; the class/semester; the URL of this assignment page.

• Your file utils.php will contain function-definitions for each function below, plus the function test (as we had in class; include a comment citing this function, and a link to the page where you found it).
  You should be able to invoke, from the command line, php utils.php and get no output.

• Your file utils-test.php will call require_once('utils.php'); near the start. The rest of the file will just be calls to test (as we wrote in class). (It an also have a few echo statements.) You should be able to invoke, from the command line, php utils-test.php and get output indicating that the tests were run (hopefully successfully).

  Your file utils-test.php may also contain some written-answers to other questions, as directed below. (Those answers are nearly test-cases, which is why they'll be put in that file.)

• Here is a sample (had the homework just asked you to write blend): utils-test.php and utils.php.
  Note that although these files use javadoc for their documentation, you don't need to do so (but you do need a similar level of documentation). You may use those two files as a starting point, but please (a) update the comments at the top of the file — I'll take off points if you turn in a file whose comments claim I am the file's author!; and (b) cite the code for test, with a URL of where you got it from.
• Submit your two files on D2L for hw02.

1. (10pts) Write a php function string pluralize( int $num, string $noun ) which returns a user-friendly version of a number+noun: pluralize( 7, "t-shirt" ) === "7 t-shirts". We'll use this function on future web-pages, when (say) confirming somebody's order.
   1. Be sure to include at least three test cases, each covering a different situation.
      (The noun will never be the empty string, so you don't even need to check for that. But what other corner-cases should you handle? (Many students lose points by not thinking through test cases closely enough, and then not having code that covers such corner cases.)
   2. You can presume that a plural is always formed by just adding “s” to any word.
      (Extra credit, open-ended: incorporate more-correct rules about how plurals are formed in English.)
2. (10pts) Write a function string hyperlink( string $url, string-or-boolean $linkTxt ) which returns a string of html. If the provided $linkTxt is false (instead of a string), then use the $url as the link text.
   hyperlink( "http://www.gutenberg.org", "free books!" ) === "<a href='http://www.gutenberg.org'>free books!</a>"
   hyperlink( "myLocalFile.html", false ) === "<a href='myLocalFile.html'>myLocalFile.html</a>"

   Note that this is just a regular ol' function that takes in strings and returns strings!
   The fact that the strings happen to have angle-brackets in them means that the result might be useful to people generating html, but the function itself does't really care.

   (You don't need to come up with additional test cases, but you do need to actually include these tests or their equivalent. You can assume that neither string is ever empty.)

   Note how the input strings don't contain any quote-characters, but the returned result does (since HTML attributes must be quoted). I recommend that your generated html uses single quote marks around attributes, but you'll get full credit for either single- or double-quote marks, as long as it is valid HTML. Make sure your test case(s) express exactly what you want the desired output should be!

3. (10pts) Thumbnails:
   1. What is the html element for an image with source pony.jpg (in the same directory), that is 300px wide?
      Include your answer in a comment, in your test-file.
   2. What is the html for such an image which is also a link — where the link would take you to that file (not a html page — just that file).
      Include your answer in a comment, in your test-file.

   3. Make a test-case for thumbnail("pony.jpg",300); the expected-output should be a string that happened to be your answer.
      You don't need further test-cases for this problem.

      Pay close attention to the exact spacing you want to have. I recommend using single-quotes (') around the attribute-values. (We'll discuss this more on Monday.)

   4. Finally, implement the function thumbnail that takes in a string (a URL) and a number (the width in pixels), and returns a string that is an html link containing an image.

      For full credit, your function should call hyperlink as already written!

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©2012, Ian Barland, Radford University Last modified 2013.Feb.02 (Sat)

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