CIT041J - Forms Exercise

Use the “view source” option in your browser to get the source of the base file that you should use for your solution.

The conversion should “follow" the last field where you entered a number. Example:

1. Type 212 in the English area.
2. Select Fahrenheit <- -> Celsius from the drop-down menu.
3. The number 100 appears in the Metric area.
4. Select pounds <- -> kilograms from the drop-down menu.
5. Because the last typing was in the English area, the Metric area changes to 96.1632.
6. Type 100 in the Metric area. Since this is the most recent change, the corresponding number of pounds (220.46) appears in the English area.

Plan before you write! Do not sit down at the keyboard and start writing this code; it is not trivial. Write a flowchart or pseudo-code before you attempt this program. Remember: Programs written at the keyboard look like it.

Hints

• You will need to use a variable to keep track of which field last had a number entered in it.
• Pass a parameter to the conversion function to tell it which field has changed.
• You don't need to give a value to the <option> elements; you only need to know which conversion was chosen. Extra hint: use .selectedIndex
• Here are the conversion factors you will need for English to Metric

  Fahrenheit to Celsius:	C = ((F - 32) / 9) * 5
  miles to kilometers:	km = miles * 1.609344
  pounds to kilograms:	kg = pounds * 0.4536
  miles per gallon to kilometers per liter:	kpl = mpg * 1.609344 / 3.785

• Here are the conversion factors you will need for Metric to English:

  Celsius to Fahrenheit:	F = ((C / 5) * 9) + 32
  kilometers to miles:	miles = km * 0.62137
  kilograms to pounds:	pounds = kg * 2.2046
  kilometers per liter to miles per gallon:	mpg = kpl * 0.62137 * 3.785