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JavaScript - I create a function which can sum(start,end) and I want it to return "ERROR" when input is String but it doesn't work

here is what I've tried
`
function sumAll(start, end) {
let average = Math.abs(start + end) / 2;
let numberOfTerms = Math.abs(end - start) / 1 + 1;
if (start >= 0 && end >= 0 ) {
return Math.abs(average * numberOfTerms);
} else if(typeof start === 'string' || typeof end === 'string'){
return "ERROR";
}else{
return "ERROR";
}
}
console.log("sumAll(10, '90') =" + sumAll(10, "90")); // I want this to return "ERROR" because "90" is String
console.log("sumAll(10, '90') =" + sumAll(10, "x"));// this works
`
but when I change input to "x" it works just fine. I think I miss something.
feel free to tell me anything, I'm a beginner. I'd love to learn new thing.

it is a great rule of thumb to do the validation first before anything else. because Javascript is a high level language, string that has only digit(s) in it like "1" or "100" or "123", Javascript will convert them into number automatically when you do comparison, subtraction, multiplication and division with other number or digit(s) only string. but not addition, because Javascript will concatenate the string instead.
function sumAll(start, end) {
if(typeof start !== "number" || typeof end !== "number") return "ERROR";
...
}

How to sanitize (digits and hyphen only) and auto-format (hyphen and leading zeros insertion) a text input value while typing and/or pasting text?

There are similar questions on SO, but mine is a bit unique. I want to limit an input text field to 9 characters in length (currently solved with maxlength attribute), only allow typing in numeric values and the hyphen character. Sort of handled with this code returning "True":
/^\d*\-?\d*$/.test(value)
Where I'm stuck is, I want the input text field to auto-format the value as the user types in the format:
12345-123
Where it's 5 digits (may have leading zeros or not depending on how user inputs it), followed by a hyphen, then always 3 digits. I'd like it to pad the first 5 with zeros if user enters something like "123-495" manually, so it would become "00123-495".
I'm not sure how to add in the auto-zero padding, or placement of the hyphen automatically.
Not opposed to using jQuery, but would prefer vanilla.
EDIT: Thought it might be useful to add. This is for an access card number entry box. So value will always be a positive number, and will always have 3 digits after the single hyphen. The card number will always be 5-digits in length, but again, may be padded with zeros to make it that length. Ideal output should always be "xxxxx-xxx".
EDIT 2: This seems to work, but there's an issue where user can enter non-numeric characters at first and after the 1st entry, only then does it clear it out. It also doesn't seem to let me hit backspace past the hyphen... Is there a way to prevent it from allowing alpha characters completely?
// Restricts input for the given textbox to the given inputFilter function.
function setInputFilter(textbox, inputFilter) {
["input", "keydown", "keyup", "mousedown", "mouseup", "select", "contextmenu", "drop"].forEach(function(event) {
textbox.addEventListener(event, function() {
if (inputFilter(this.value)) {
// Current value
new_val = '';
if (this.value.includes('-') && this.value.slice(this.value.indexOf('-')).length == 4) {
console.log("Value not hyphenated yet");
pad_needed = 5 - this.value.indexOf('-');
console.log('Pad needed: ' + pad_needed);
new_val = this.value.padStart(9, '0');
this.value = new_val;
} else if (this.value.length >= 5 && this.value.includes('-') && this.value.slice(this.value.indexOf('-')).length == 4) {
if (this.value.slice(5, 1) == '-') {
// Already a hyphen added, just add rest of numbers
new_val = this.value.slice(0, 6) + this.value.slice(6);
} else {
// Needs hyphen added
new_val = this.value.slice(0, 5) + '-' + this.value.slice(6);
}
this.value = new_val;
} else if (this.value.length >= 5 && !this.value.includes('-')) {
// Needs hyphen added
new_val = this.value.slice(0, 5) + '-' + this.value.slice(6);
this.value = new_val;
}
this.oldValue = this.value;
this.oldSelectionStart = this.selectionStart;
this.oldSelectionEnd = this.selectionEnd;
} else if (this.hasOwnProperty("oldValue")) {
this.value = this.oldValue;
this.setSelectionRange(this.oldSelectionStart, this.oldSelectionEnd);
} else {
this.value = "";
}
});
});
}
setInputFilter(document.getElementById("card-number"), function(value) {
return /^\d*\-?\d*$/.test(value); // Allow digits and '-' only
});

function getSanitizedInputValue(value) {
value = value
.trim()
.replace(/^[-]+/, '')
.replace(/[-]+/, '-');
let [
first,
...rest
] = (value.match(/[-\d]+/g) ?? [])
.join('')
.split('-')
let joiner = '';
if (first.length >= 6) {
joiner = '-';
rest.unshift(first.slice(5));
first = first.slice(0, 5);
} else if (rest.length >= 1) {
joiner = '-';
first = first.padStart(5, '0');
}
return [
first,
rest.join(''),
]
.join(joiner)
.slice(0,9);
}
function handleInput({ currentTarget: control }) {
const { value: recentValue, selectionStart, selectionEnd } = control;
const regXHasHyphen = /-/;
const sanitizedValue = getSanitizedInputValue(recentValue);
const sanitizedLength = sanitizedValue.length;
const recentLength = recentValue.length;
const positionDelta = (
(recentLength <= 5) &&
(sanitizedLength >= 6) &&
(sanitizedLength - recentLength)
) || (
!regXHasHyphen.test(recentValue) &&
regXHasHyphen.test(sanitizedValue) &&
1
) || 0;
control.value = sanitizedValue;
control.selectionStart =
Math.min(sanitizedLength, (selectionStart + positionDelta));
control.selectionEnd =
Math.min(sanitizedLength, (selectionEnd + positionDelta));
}
document
.querySelector('[type="text"]')
.addEventListener('input', handleInput);
<input type="text" maxlength="9" />

How to match PHP's explode(';',$s,3) to s.split(';',3) in JavaScript?

If you run an explode in PHP with the resulting array length limited, it will append the remainder of the string to the last element. This is how exploding a string should behave, since nowhere in the split am I saying that I want to discard my data, just split it. This is how it works in PHP:
# Name;Date;Quote
$s = 'Mark Twain;1879-11-14;"We haven\'t all had the good fortune to be ladies; we haven\'t all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground."';
$a = explode(';',$s,3);
var_dump($a);
array(3) {
[0]=>
string(10) "Mark Twain"
[1]=>
string(10) "1879-11-14"
[2]=>
string(177) ""We haven't all had the good fortune to be ladies; we haven't all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground.""
}
However, if you run the same code in JavaScript:
> var s = 'Mark Twain;1879-11-14;"We haven\'t all had the good fortune to be ladies; we haven\'t all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground."'
undefined
> var a = s.split(';',3);
undefined
> a
[ 'Mark Twain',
'1879-11-14',
'"We haven\'t all had the good fortune to be ladies' ]
This makes absolutely no sense, because the whole point of splitting a string is to treat the final portion of the string as a literal, instead of delimited. JavaScript's split with a limit is the exact same as:
# In PHP
$a = array_slice(explode(';',$s), 0, 3);
# Or in JavaScript
var a = s.split(';').slice(0, 3);
If the user in JavaScript only wanted to make use of the first two elements in this array, whether the array is split or not doesn't matter. The first two elements will always have the same value no matter what. The only element that changes, is the last element of the split array.
If the native split with limit method in JavaScript can be replicated using a slice, then what value does it provide?
But I digress, what is the most efficient way to replicate the explode functionality in PHP? Removing each element as a substring until the last element is reached, splitting the entire string and then concatenating the remaining elements, getting the location of the n - 1 delimiter and getting a substring of that, or any other solution I haven't thought of?

According documentation the split function accepts two arguments:
string.split(separator, limit)
However this still gives not the result you want because:
The second parameter is an integer that specifies the number of
splits, items after the split limit will not be included in the array
However, I noticed that the ';' in the text has a space behind it. So you could use a regex.
var s = 'Mark Twain;1879-11-14;"We haven\'t all had the good fortune to be ladies; we haven\'t all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground."'
var a = s.split(/;(?! )/,3)
console.log(a);
The Regex (/;(?! ) splits all ';' except if there is a space behind it.
Hope this helps!

Loctus.io got you covered, they ported php's explode, and a great number of other php functions to javascript
usage:
$s = 'Mark Twain;1879-11-14;"We haven\'t all had the good fortune to be ladies; we haven\'t all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground."';
"Mark Twain;1879-11-14;"We haven't all had the good fortune to be ladies; we haven't all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground.""
$a = explode(';',$s,3);
content of $a as reported by Chrome's javascript console:
0: "Mark Twain"
1: "1879-11-14"
2: ""We haven't all had the good fortune to be ladies; we haven't all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground.""
length: 3
, source: http://locutus.io/php/strings/explode/
function explode (delimiter, string, limit) {
// discuss at: http://locutus.io/php/explode/
// original by: Kevin van Zonneveld (http://kvz.io)
// example 1: explode(' ', 'Kevin van Zonneveld')
// returns 1: [ 'Kevin', 'van', 'Zonneveld' ]
if (arguments.length < 2 ||
typeof delimiter === 'undefined' ||
typeof string === 'undefined') {
return null
}
if (delimiter === '' ||
delimiter === false ||
delimiter === null) {
return false
}
if (typeof delimiter === 'function' ||
typeof delimiter === 'object' ||
typeof string === 'function' ||
typeof string === 'object') {
return {
0: ''
}
}
if (delimiter === true) {
delimiter = '1'
}
// Here we go...
delimiter += ''
string += ''
var s = string.split(delimiter)
if (typeof limit === 'undefined') return s
// Support for limit
if (limit === 0) limit = 1
// Positive limit
if (limit > 0) {
if (limit >= s.length) {
return s
}
return s
.slice(0, limit - 1)
.concat([s.slice(limit - 1)
.join(delimiter)
])
}
// Negative limit
if (-limit >= s.length) {
return []
}
s.splice(s.length + limit)
return s
}
edit: if you for some reason need/want a smaller implementation, here's 1 i made in response to the comments:
function explode(delimiter, string, limit) {
var spl = string.split(delimiter);
if (spl.length <= limit) {
return spl;
}
var ret = [],i=0;
for (; i < limit; ++i) {
ret.push(spl[i]);
}
for (; i < spl.length; ++i) {
ret[limit - 1] += delimiter+spl[i];
}
return ret;
}

Alright, I created 4 alternative versions of the PHP split string algorithm, along with the two provided by #hanshenrik, and did a basic benchmark on them:
function explode1(delimiter, str, limit) {
if (limit == null) {
return s.split(delimiter);
}
var a = [];
var lastIndex = -1;
var index = 0;
for (var i = 0; i < limit; i++) {
index = str.indexOf(delimiter, lastIndex + 1);
if (i == limit - 1) {
a.push(str.substring(lastIndex + 1));
} else {
a.push(str.substring(lastIndex + 1, index));
}
lastIndex = index;
}
return a;
}
function explode2(delimiter, str, limit) {
if (limit == null) {
return s.split(delimiter);
}
var a = str.split(delimiter);
var ret = a.slice(0, limit - 1);
ret.push(a.slice(limit - 1).join(delimiter));
return ret;
}
function explode3(delimiter, str, limit) {
if (limit == null) {
return s.split(delimiter);
}
var a = s.split(delimiter, limit - 1);
var index = 0;
for (var i = 0; i < limit - 1; i++) {
index = s.indexOf(delimiter, index + 1);
}
a.push(str.substring(index + 1));
return a;
}
function explode4(delimiter, str, limit) {
if (limit == null) {
return s.split(delimiter);
}
var a = str.split(delimiter, limit - 1);
a.push(str.substring(a.join(delimiter).length + 1));
return a;
}
function explode5(delimiter, string, limit) {
// discuss at: http://locutus.io/php/explode/
// original by: Kevin van Zonneveld (http://kvz.io)
// example 1: explode(' ', 'Kevin van Zonneveld')
// returns 1: [ 'Kevin', 'van', 'Zonneveld' ]
if (arguments.length < 2 ||
typeof delimiter === 'undefined' ||
typeof string === 'undefined') {
return null
}
if (delimiter === '' ||
delimiter === false ||
delimiter === null) {
return false
}
if (typeof delimiter === 'function' ||
typeof delimiter === 'object' ||
typeof string === 'function' ||
typeof string === 'object') {
return {
0: ''
}
}
if (delimiter === true) {
delimiter = '1'
}
// Here we go...
delimiter += ''
string += ''
var s = string.split(delimiter)
if (typeof limit === 'undefined') return s
// Support for limit
if (limit === 0) limit = 1
// Positive limit
if (limit > 0) {
if (limit >= s.length) {
return s
}
return s
.slice(0, limit - 1)
.concat([s.slice(limit - 1)
.join(delimiter)
])
}
// Negative limit
if (-limit >= s.length) {
return []
}
s.splice(s.length + limit)
return s
}
function explode6(delimiter, string, limit) {
var spl = string.split(delimiter);
if (spl.length <= limit) {
return spl;
}
var ret = [],i=0;
for (; i < limit; ++i) {
ret.push(spl[i]);
}
for (; i < spl.length; ++i) {
ret[limit - 1] += delimiter+spl[i];
}
return ret;
}
var s = 'Mark Twain,1879-11-14,"We haven\'t all had the good fortune to be ladies; we haven\'t all been generals, or poets, or statesmen; but when the toast works down to the babies, we stand on common ground."'
console.log(s);
console.time('explode1');
var a1 = explode1(',', s, 3);
//console.log(a1);
console.timeEnd('explode1');
console.time('explode2');
var a2 = explode2(',', s, 3);
//console.log(a2);
console.timeEnd('explode2');
console.time('explode3');
var a3 = explode3(',', s, 3);
//console.log(a3);
console.timeEnd('explode3');
console.time('explode4');
var a4 = explode4(',', s, 3);
//console.log(a4);
console.timeEnd('explode4');
console.time('explode5');
var a5 = explode5(',', s, 3);
//console.log(a5);
console.timeEnd('explode5');
console.time('explode6');
var a6 = explode6(',', s, 3);
//console.log(a6);
console.timeEnd('explode6');
The two best-performing algorithms was explode4 principally, with explode3 a close second in multiple iterations of the benchmark:
$ node explode1.js && node explode2.js && node explode3.js && node
explode4.js && node explode5.js && node explode6.js
explode1: 0.200ms
explode2: 0.194ms
explode3: 0.147ms
explode4: 0.183ms
explode5: 0.341ms
explode6: 0.162ms
You can run your own benchmarks, but with my tests I can confirm that splitting an array by n - 1 and then getting an index from joining the resulting array is the fastest algorithm matching explode in PHP.
EDIT: It turns out that the garbage collector biased how each successive function was measured, so I split them off into their own individual files and re-ran the benchmarking a few times. It seems explode3 is the best performing, not explode4, but I won't make a decision that I'm not completely sure of.

Javascript Function to Format as Money [duplicate]

This question already has answers here:
How to format a number with commas as thousands separators?
(50 answers)
Closed 6 years ago.
I have a script where I pass it a string, and it'll return that string formatted as dollars. So if I send it "10000" it'll return "$10,000.00" Now the problem is that when I send it "1000000" ($1 million) it returns "$1,000.00" because it's only setup to parse based on one set of zeros. Here's my script, how can I adjust it to account for two sets of zeros ($1 million) ??
String.prototype.formatMoney = function(places, symbol, thousand, decimal) {
if((this).match(/^\$/) && (this).indexOf(',') != -1 && (this).indexOf('.') != -1) {
return this;
}
places = !isNaN(places = Math.abs(places)) ? places : 2;
symbol = symbol !== undefined ? symbol : "$";
thousand = thousand || ",";
decimal = decimal || ".";
var number = Number(((this).replace('$','')).replace(',','')),
negative = number < 0 ? "-" : "",
i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + "",
j = (j = i.length) > 3 ? j % 3 : 0;
return negative + symbol + (j ? i.substr(0, j) + thousand : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousand) + (places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : ""); };
Thanks in advance for any useful information!

function formatMoney(number) {
return number.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
}
console.log(formatMoney(10000)); // $10,000.00
console.log(formatMoney(1000000)); // $1,000,000.00

Give this a shot it looks for a decimal separator but you can remove that part if youd like:
{
number = parseFloat(number);
//if number is any one of the following then set it to 0 and return
if (isNaN(number)) {
return ('0' + '{!decimalSeparator}' + '00');
}
number = Math.round(number * 100) / 100; //number rounded to 2 decimal places
var numberString = number.toString();
numberString = numberString.replace('.', '{!decimalSeparator}');
var loc = numberString.lastIndexOf('{!decimalSeparator}'); //getting position of decimal seperator
if (loc != -1 && numberString.length - 2 == loc) {
//Adding one 0 to number if it has only one digit after decimal
numberString += '0';
} else if (loc == -1 || loc == 0) {
//Adding a decimal seperator and two 00 if the number does not have a decimal separator
numberString += '{!decimalSeparator}' + '00';
}
loc = numberString.lastIndexOf('{!decimalSeparator}'); //getting position of decimal seperator id it is changed after adding 0
var newNum = numberString.substr(loc, 3);
// Logic to add thousands seperator after every 3 digits
var count = 0;
for (var i = loc - 1; i >= 0; i--) {
if (count != 0 && count % 3 == 0) {
newNum = numberString.substr(i, 1) + '{!thousandSeparator}' + newNum;
} else {
newNum = numberString.substr(i, 1) + newNum;
}
count++;
}
// return newNum if youd like
};

JS calculator issue. Wrong Answer

I'm writing a one-line calculator, that has the basic functions (+ - * /). I have done this before, but now I keep getting wrong answers, and I can't find my mistake. Here is my code:
var seq = document.getElementById('sequence').value;
var allNums = [];
var i = 0, allSigns = [];
var currentNums = "";
for (i = 0; i< seq.length; i++)
{
if (seq[i] != "+" && seq[i] != "-" && seq[i] != "*" && seq[i] != "/")
{
currentNums+=seq[i];
}
else
{
allNums.push(Number(currentNums));
currentNums="";
allSigns.push(seq[i]);
}
}
allNums.push(Number(currentNums));
var result = 0;
for (i = 0; i < allNums.length; i++)
{
if (allSigns[i] == '+')
result+=Number(allNums[i]);
else if (allSigns[i] == "-")
result-=Number(allNums[i]);
else if (allSigns[i] == "*")
result*=Number(allNums[i]);
else if (allSigns[i] == "/")
result/=parseInt(allNums[i]);
else
{
alert("The result is: " + result);
break;
}
}
All of this code is in a function, called calculate. The func is triggered by a button, and the sequence comes from an input.

Though there are numerous shortcomings with this simple calculator that may or may not be a problem (depending on what you want to do with it), one issue is that your allSigns array values aren't being associated with the correct allNums array values.
Take a look at this example. In the console, you can see that the sign associated with the 6 is the plus sign, while the operator associated with 2 is undefined. This isn't what we want, of course. What we want is to add the two to the six.
The fix for this issue would be always adding allNums[0] to the result from the start. This sets up our result to be operated upon by anything following it. In this case, we start off with 6.
Next what we need to do is shift the position of each value of allSigns down by one, lining up the operator with the value after it, and not before it. So, in the example above, we'd have + associated with 2, so it'd add the two to the six.
This JSFiddle shows the fix for this specific case.

http://jsbin.com/obasix/3/edit
There are not as many signs as numbers. So therefore, if there are 2 numbers and 1 sign, it will calculate 5 + and then end.
You should start with the result bring the first number.
And then iterate with the remaining numbers and calculate accordingly.
var seq = "5+4";
var allNums = [];
var i = 0, allSigns = [];
var currentNums = "";
for (i = 0; i< seq.length; i++)
{
if (seq[i] != "+" && seq[i] != "-" && seq[i] != "*" && seq[i] != "/")
{
currentNums+=seq[i];
}
else
{
allNums.push(Number(currentNums));
currentNums="";
allSigns.push(seq[i]);
}
}
allNums.push(Number(currentNums));
var result = allNums[0];
for (i = 1; i <= allNums.length; i++)
{
if (allSigns[i-1] == '+')
result+=Number(allNums[i]);
else if (allSigns[i-1] == "-")
result-=Number(allNums[i]);
else if (allSigns[i-1] == "*")
result*=Number(allNums[i]);
else if (allSigns[i-1] == "/")
result/=parseInt(allNums[i]);
else
{
alert("The result is: " + result);
break;
}
}

Try this library https://github.com/notshekhar/calculate.js
Example
<script src="https://raw.githubusercontent.com/notshekhar/calculate.js/main/calculate.js"></script>
<script>
let add = calculate(1, 1, "+") // add -> 2
let sub = calculate(1, 1, "-") // sub -> 0
let mul = calculate(1, 1, "*") // mul -> 1
let div = calculate(1, 1, "/") // div -> 1
let mod = calculate(1, 1, "%") // mod -> 0
</script>