Javascript function error.

and180y

Hi Richard, thanks so much. Yes basically the page has all 7 days, a check box if open that day and input boxes for opening and closing hours and the hours open. I will use the code above. thankyou.

DerekT P

Saw this thread, and suddenly had awful deja vu back to 17th Feb 1999[^] (This is one of my all-time favourite Dilberts, simply because I see it in real life so often!)

jkirkerx

I know I'm late on this, but 0 - 0 is 0 opening time is 0 or 12 midnight closing time is 0 or 12 midnight so you get 0

If it ain't broke don't fix it Discover my world at jkirkerx.com

and180y

I was just glad the code worked. :) :)

jkirkerx

:) I wrote a similar function for showing that my business is open, based on open and closed hours in TypeScript. It drove me nuts, was always off by an hour, Daylight savings. I'll get back to it soon, now that I have more experience in TypeScript. :(

setStoreHours(): void {
const date = new Date();
const newDate = new Date(date.getTime() + date.getTimezoneOffset() * 60 * 1000);
const offset = date.getTimezoneOffset() / 60;
this.hourOfDay = date.getHours();
this.dayOfWeek = date.getDay();
switch (this.dayOfWeek) {
case 0:
// Sunday
this.storeStatus = "Closed";
break;
case 1:
// Monday
if (this.hourOfDay > 8 && this.hourOfDay < 17) {
this.storeStatus = "Open";
}
break;
case 2:
// Tuesday
if (this.hourOfDay > 8 && this.hourOfDay < 17) {
this.storeStatus = "Open";
}
break;
case 3:
// Wednesday
if (this.hourOfDay > 8 && this.hourOfDay < 17) {
this.storeStatus = "Open";
}
break;
case 4:
// Thursday
if (this.hourOfDay > 8 && this.hourOfDay < 17) {
this.storeStatus = "Open";
}
break;
case 5:
// Friday
if (this.hourOfDay > 8 && this.hourOfDay < 15) {
this.storeStatus = "Open";
}
break;
case 6:
// Saturday
this.storeStatus = "Closed";
break;
default:
this.storeStatus = "Closed";
}
}

If it ain't broke don't fix it Discover my world at jkirkerx.com

and180y

Where's the best place to learn how to write functions and class functions. I've ran through the courses Richard suggested above but none seem to be taking me where I need to be or am I trying to walk before I can run? :-) To me this should run but it's not returning a value, (or I'm not grasping how to get it to do so)

$(function(){
$("#current-charge").keyup(function(){
var time = $("#time-allowed").val();
var current = $("#current-charge").val();
$("breakeven").html(time * current);
})
})

jkirkerx

That's JQuery like syntax. IMO, Don't waste your time learning JQuery, I've been there and done that already. JQuery is obsolete now, because modern browsers support modern JavaScript. JQuery adds 3 Lbs to your first page download, and is very heavy in weight, in exchange to write shorthand JavaScript. The reason your not absorbing or moving faster with knowledge is because your looking at shorthand JavaScript/JQuery examples, and trying to understand and copy them. These are very advanced writing skills. You should start with entry level skill writing, and when you get that down, move to shorthand. I would of wrote it like this, for a beginner example. ES6 Use HTML to bind the event to the button, and run calcTime(). Use camel case to label things eg. calcTime vs CalcTime vs calc-time let has replaced var use const instead of var or let to when something that is constant. Try not to make a lot of const, see how I did it in one line ES6 Example

Calculate

function calcTime() {

// Make references to input elements
const time = document.getElementById("currentCharge"),
current = document.getElementById("timeAllowed"),
breakEven = document.getElementById("breakEven");

// Get the element values, convert to number/float
// By default, values are strings, and don't do math well.
let t = parseFloat(time.value);
let c = parseFloat(current.value);

// Perform the equation
let bE = t * c;

// Output the equation
breakEven.innerHTML = bE.toString();

}

JavaScript comes in many flavors now. I think you want ECMAScript 6, ES6, ECMAScript 2015 From there, you can branch out to TypeScript, Node, etc. I don't know of a good learning course, but you need to stick to one version in order to learn. And when searching for help on the internet, find examples in ES6; learn to identity ES6 examples, and then code and test.

If it ain't broke don't fix it Discover my world at jkirkerx.com

and180y

Sorry, I think I deleted my reply just as you replied to it. :sigh: :doh: :doh:

jkirkerx

That's JQuery like syntax. IMO, Don't waste your time learning JQuery, I've been there and done that already. JQuery is obsolete now, because modern browsers support modern JavaScript. JQuery adds 3 Lbs to your first page download, and is very heavy in weight, in exchange to write shorthand JavaScript. The reason your not absorbing or moving faster with knowledge is because your looking at shorthand JavaScript/JQuery examples, and trying to understand and copy them. These are very advanced writing skills. You should start with entry level skill writing, and when you get that down, move to shorthand. I would of wrote it like this, for a beginner example. ES6 Use HTML to bind the event to the button, and run calcTime(). Use camel case to label things eg. calcTime vs CalcTime vs calc-time let has replaced var use const instead of var or let to when something that is constant. Try not to make a lot of const, see how I did it in one line ES6 Example

Calculate

function calcTime() {

// Make references to input elements
const time = document.getElementById("currentCharge"),
current = document.getElementById("timeAllowed"),
breakEven = document.getElementById("breakEven");

// Get the element values, convert to number/float
// By default, values are strings, and don't do math well.
let t = parseFloat(time.value);
let c = parseFloat(current.value);

// Perform the equation
let bE = t * c;

// Output the equation
breakEven.innerHTML = bE.toString();

}

JavaScript comes in many flavors now. I think you want ECMAScript 6, ES6, ECMAScript 2015 From there, you can branch out to TypeScript, Node, etc. I don't know of a good learning course, but you need to stick to one version in order to learn. And when searching for help on the internet, find examples in ES6; learn to identity ES6 examples, and then code and test.

If it ain't broke don't fix it Discover my world at jkirkerx.com

and180y

Have added some more elements (not in use at present) but still not getting the breakeven to calculate.

<button type="button" onBlur="calcTime()">Calculate</button>

function calcTime() {

// Make references to input elements
const time = document.getElementById("timeAllowed"),
current = document.getElementById("currentCharge"),
breakEven = document.getElementById("breakEven"),
tier1 = document.getElementById ("tier1"),
tier2= document.getElementById ("tier2");

// Get the element values, convert to number/float
// By default, values are strings, and don't do math well.
let t = parseFloat(time.value);
let c = parseFloat(current.value);

// Perform the equation
let bE = t * c;

// Output the equation
breakEven.innerHTML = bE.toString();

}</pre></x-turndown>

Lost User

Look at the id names you are using in the HTML against the ones you are using in the Javascript. You need to read through your code more closely.

jkirkerx

You got it wrong ... You are fresh at this ;) I can't test this at the moment, but it should work. I hope it does.

function calcTime() {

// Make references to input elements
const time = document.getElementById("time"),
current = document.getElementById("current"),
tier1 = document.getElementById ("tier1"),
tier2= document.getElementById ("tier2"),
breakEven = document.getElementById("breakEven"),
results = document.getElementById("results");

// Get the element values, convert to number/float
// By default, values are strings, and don't do math well.
let t = parseFloat(time.value);
let c = parseFloat(current.value);

// Perform the equation
let bE = t * c;

// Output the equation to the span element, remove the comments below
console.log("breakEven=", bE); // Diagnostics, hit F12 on your keyboard and select console
results.innerHTML = bE.toString(); // innerHTML is for a span tag, value is textbox
}

Calculate

0

If it ain't broke don't fix it Discover my world at jkirkerx.com

and180y

Jkirkerx, not sure why but your post vanished. I tried it but no luck. Going to change a few things so will keep you updated, thanks for your help thus far. :)

and180y

Thanks Richard, you were right. In my haste I lost focus. :)