Computing Concepts 106 A Exam 3 Study Guide ANSWERS
Tom Linton, Fall 2002, Central College
  1. Using FrontPage, write the HTML file to create a web page similar to the one below (don't worry about the border, it's there only to outline the page):
    Note: The form is named pokerForm. The text boxes are named card1box, card2box, card3box, card4box, and card5box. The 2 radio buttons under card 1 are named card1, the 2 radio buttons under card2 are named card2 and so on. If a user clicks the "Draw Cards" button the function named replaceCards should be called (but do not worry about defining this function, just make sure that it gets called when the top button gets clicked). The form above shows the initial contents of the page when it loads (so the cards shown should be displayed when the page loads). 

    Here's the solution, you'll have top view its source to see the HTML.


  1. Write a (very odd) version of the replaceCards function for the form above. It will ignore all the radio buttons and simply ask the user for a number from 1 to 10 (with a prompt command). If the number they enter is from 3 to 7 (inclusive), change the value displayed for the second card to "Qd", otherwise, change the 10 and Jack of diamonds to the 7 of clubs and 7 of hearts respectively.
      2. function replaceCards(){
          var num = prompt("Enter a number from 1 to 10","");
          num = parseFloat(num);
          if ( (num < 1) || (num > 10)){
              num = prompt("I said from 1 to 10, try again!","");
          }
          if ( (num >= 3) && (num <= 7) ){
              document.pokerForm.card2box.value="Qd";
          }
          else {
              with (document.pokerForm){
                  card3box.value = "7c";
                  card1box.value = "7h";
              }
          }
      }
       
  2. Given the form below (with the names corresponding in the obvious way to the various form elements), what (exactly) gets displayed by the JavaScript statements:
      3. var theName = document.myForm.nameBox.value;
      var n1 = document.myForm.number1Box.value;
      var n2 = document.myForm.number2Box.value;
      document.write("Hi " + theName + "your sum is " + n1 + n2 + "<BR>Have a great day!");

      The result is:
      Hi Tom Lintonyour sum is 1255
      Have a great day!


Name: 

Number 1:   Number 2: 

  1. Assume that the form above has a push-button whose onClick attribute calls the function work(). Also assume there is a multi-line text area (at the bottom of the form) named output. Write the JavaScript statements needed to define the work function, so that when the user clicks the button, a message similar to:
      2. Thanks for shopping at Grandma Lumpits Tom Linton.
      You ordered:
      --12 chocolate chip cookies
      --55 biscuits
      and your total is $5.0
    gets printed in the multi-line text area named output. Note: the bold quantities above are replaced by (non-bold versions of) their entries in the form. The cookies are .05 each and the biscuits are .08 each. By sure to have the newlines present in the output.
       
      function work() {
          with (document.myForm){
              var name = nameBox.value;
              var numCookies = parseFloat(number1Box.value);
              var numBiscuits = parseFloat(number2Box.value);
          }
          var message = "Thanks for shopping at Grandma Lumpits " + name + "\n";
          message = message + "You ordered:\n";
          message = message + "--" + numCookies + " chocolate chip cookies\n";
          message = message + "--" + numBiscuits + " biscuits\n";
          message = message + "and your total is $" + (.05*numCookies + .08*numBiscuits);
          document.myForm.output.value = message;
      }
  2. Write a JavaScript statement that sets the background color of the web page to #CC00AA.
           document.bgColor = #CC00AA;
  3. Write JavaScript statements that ask the user for a number form 1 to 50. If they enter a bad value (less than 1, or greater than 50), use an alert statement to inform them of their mistake and re-ask them for another value. Their number represents the number of bags of coffee they would like to buy. Print out a message that tells them their total price ($4 per bag, plus 6% tax).
      4. var num = prompt("Enter a number from 1 to 50","");
      num = parseFloat(num);
      if ( (num < 1) || (num>50) ){
          alert("I said from 1 to 50. Once more smoothy.");
          num = prompt("Enter a number from 1 to 50","");
          num = parseFloat(num);
      }
      var cost = 4*num;
      cost = cost + cost*.06;
      document.write("Your " + num + " bags of coffee have a total price of");
      document.write(" $" + cost + ".");
  4. Write a JavaScript statement that sends the user back 2 windows in their browser's history.
      5. window.history.go(-2);
  5. Assume every deck object has:
    6. If myDeck and yourDeck are deck objects (or variables) write JavaScript statements that assign the face of myDeck's card6 to the face of yourDeck's card2, if card1 in myDeck has a suit equal to hearts. If card1 in myDeck is not a heart, set the isShuffled property of myDeck to true, and set yourDeck's cardsLeft property to one less than its current value.
      if (myDeck.card1.suit == "hearts"){
          yourDeck.card2.face = myDeck.card6.face;
      }
      else{
          myDeck.isShuffled = true;
          yourDeck.cardsLeft = yourDeck.cardsLeft - 1;
      }