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Nancy Melucci
Courses Plus Student 35,157 PointsJavaScript Assert calls both alerts
I have an assignment to create an assert function to check numeric values for a simple calculator. What I've written is syntactically valid but calls both alerts, not just the one that proclaims valid or not.
Been fooling with the braces for about 2 hours. What am I missing? I want valid values to show a valid alert (or preferably nothing but I'm not that good) and invalid ones (non-numeric or less than 1) to trigger the invalid warning.
Thanks.
function assert(value) {
var result = "Epic Fail";
var description = "Invalid Value";
if ((value != "number") || (value <= 0) ) {
alert(result + ' - ' + description);
}
alert("pass");
};
8 Answers
blake guyan
8,297 Pointsyou not want to use "else"? after the if...
if ((value != "number") || (value < 0) ) { alert(result + ' - ' + description); } else alert("pass"); };
blake guyan
8,297 Pointshmm. this is a real mindbender. everything i have tried just drops me out of the function. i tried a loop
// Get a reference to the form value:
var length = document.getElementById('length').value;
var width = document.getElementById('width').value;
var height = document.getElementById('height').value;
const index = [length, width, height]
for (let i = 0; i < index.length; i += 1) {
assert.ok(index[i] != "number", "sorry " + index[i] + " is not a valid input"); assert.ok(index[i] < 0, "sorry " + index[i] + " must be a positive number" ); }
like that.. i pulled the vars out so i could access them from outside.. i did change the names but it didnt seem to cause any problems for the testing so i left them as you had written them.. this still kicks me out of the function for creating undefined things. i would love to know how this works out.
Nancy Melucci
Courses Plus Student 35,157 PointsIt's still doing it...thanks. I'll keep trying. I may post the html later on today.
blake guyan
8,297 Pointsyeah if i can see the whole thing i might be able to recreate it
Nancy Melucci
Courses Plus Student 35,157 PointsHere's the latest version...I am going to work on another project for a little while. HTML follows JS
function assert(x) {
var result = "Epic Fail";;
var description = "Invalid Value";;
if ((x != "number") || (x <= 0) ) {
alert(result + " , " + description);
} else {
//alert("pass");
};
function calculate() {
'use strict';
// For storing the volume:
var length;
var width;
var height;
var volume;
assert(length);
assert(width);
assert(height);
// Get a reference to the form value:
var length = document.getElementById('length').value;
var width = document.getElementById('width').value;
var height = document.getElementById('height').value;
volume = (length * width * height);
// Format the volume:
volume = volume.toFixed(2);
// Display the volume:
document.getElementById('volume').value = volume;
// Return false to prevent submission:
return false;
} // End of calculate() function.
// Function called when the window has been loaded.
// Function needs to add an event listener to the form.
function init() {
'use strict';
document.getElementById('theForm').onsubmit = calculate;
} // End of init() function.
window.onload = init;
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Nancy Melucci - Volume of a Box Calculator</title>
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<link rel="stylesheet" href="css/styles.css">
</head>
<body>
<!-- sphere.html -->
<form action="" method="post" id="theForm">
<fieldset>
<p>Use this form to calculate the volume of a box.</p>
<div><label for="length">Length</label><input type="text" name="length" id="length" required></div>
<div><label for="width">Width</label><input type="text" name="width" id="width"></div>
<div><label for="height">Height</label><input type="text" name="height" id="height"></div>
<div><label for="volume">Volume</label><input type="text" name="volume" id="volume"></div>
<div><input type="submit" value="Calculate" id="submit"></div>
</fieldset>
</form>
<script src="js/box.js"></script>
</body>
</html>
blake guyan
8,297 Pointsthanks, im out tonight but i will look at this when i get home
Nancy Melucci
Courses Plus Student 35,157 PointsI appreciate your taking the time whenever you can. Thanks again.
blake guyan
8,297 Pointsalso, whats the techuniversity stuff like? im a little hazy on what it actually is?
Nancy Melucci
Courses Plus Student 35,157 PointsYou mean the techuniversity stuff here at Treehouse? I am asking here related to community college classes I am taking. I hope to work on the techdegree more this summer. NJM
Nancy Melucci
Courses Plus Student 35,157 PointsI had to put it aside to work on a bigger project. As I am looking forward to having more time in the summer to work on Treehouse and outside projects (I am a college prof and this is the worst time of the term for grading and things that compete for my attention, I can't dwell on this too long. I would like to make it work, so I will return to your code soon and try it out.)
Additionally, I have a bigger and slightly more amusing project in JS. I am posting about it elsewhere. You may see it soon. Thanks.
blake guyan
8,297 Pointshaha, well i will try and keep this on my radar. if i come across something that might help me solve it i will post it here!