Exercise: Erasing circles

Modify the code in the following ways:

  • Add a method to create a string with information about a circle.
  • Add a method to determine the area of a circle.
  • Print the results of both methods to the console whenever a circle is drawn or erased.
  • As each circle is entered using the form, add it to an array.
  • Add an event listener for the erase button so that when the index in the array is provided, the corresponding circle is "erased" by having a white circle with a radius of one pixel greater drawn over it.

Note:

Hints:

  • Add the methods to the function CircleInfo.

Solution to the exercise

Here is one possible solution.

Note:

Hints:

  • undefined
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window.onload = startFunction;
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<!DOCTYPE html>
<html lang="en">
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