8db49a24a3
Remove the need to specify the current URL in order to style the selected item in the navbar
30 lines
1015 B
JavaScript
30 lines
1015 B
JavaScript
document.addEventListener("keyup", function(event) {
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// stop any code that may normally run when enter key pressed
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event.preventDefault();
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// if enter key is pressed, run Luhn algorithm
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if (event.keyCode === 13) {
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checkNumber();
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} else {
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// if number in input field is being edited, remove previous number evaluation message
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$("#validation_message").html(null);
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}
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});
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// function for validating number entered with Luhn algorithm
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function checkNumber() {
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// retrieve digits & reverse
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var digits = document.getElementsByTagName("input")[0].value.split("").reverse(), sum = 0;
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digits.forEach(function(currentDigit, index) {
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newDigit = Number(currentDigit);
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if (index % 2 == 1) {
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if ((newDigit *= 2) > 9) {
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newDigit -= 9;
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}
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}
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sum += newDigit;
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});
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// displays evaluation message
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$("#validation_message").html(((sum % 10) == 0) ? "Number is valid" : "Number is invalid");
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}
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