Please help with learning jQuery

Please help with learning jQuery

I have this javascript that works, but can someone show me a better way of writing it (more jQuery way if you will). When a user enters a number is two different textboxes, I need to show the percent between the two.

  2. var firstNumber = $('.numberOfStudentsParticipating').val();
  3. var secondNumber = $('.numberOfStudentsMetOutcome').val();

  5. function checkForNumber(id, numberEntered) {
  6. if (id.indexOf('txtNumberOfStudentsParticipating') > 0)
  7. firstNumber = numberEntered;

  9. if (id.indexOf('txtNumberOfStudentsMetOutcome') > 0)
  10. secondNumber = numberEntered;

  12. if (firstNumber > 0 && secondNumber > 0) {
  13. var percentage = (secondNumber / firstNumber).toFixed(4) * 100;
  14. $('.percentageOfStudents').val(percentage.toString() + "%");
  15. }

  17. if (event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || event.keyCode == 27 || event.keyCode == 13 || event.keyCode == 16 || (event.keyCode == 65 && event.ctrlKey === true) ||
  18. (event.keyCode >= 35 && event.keyCode <= 39)) {
  19. return;
  20. }
  21. else {
  22. // Ensure that it is a number and stop the keypress 
  23. if ((event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105)) {
  24. event.preventDefault();
  25. }
  26. }
  27. }