Develop Reference

how to prevent a key input from appearing in input field?

I am trying to validate user input in a text input field.
I have written a javascript function for the same purpose which fires on onkeyup event.
The goal is to only allow user input if it's a numeric value less than 100 and with at most 1 decimal place.
The function is working fine but if a enter an invalid character ,say 'a', it will flash in the input box before being removed.
What I want is that if the entered character violates the defined condition it should not appear in the input box (as it is flashing right now for a split second).
Here's my code:
function validatePercent(event) {
var txt = $("#tds_input").val();
// alert(event.source);
if (!parseInt(txt)) {
$("#tds_input").val('');
}
if (isNaN(txt / 1)) {
txt = txt.substr(0, txt.length - 1);
$("#tds_input").val(txt);
}
if (txt > 100) {
//alert(2);
txt = txt.toString();
txt = txt.substr(0, txt.length - 1);
$("#tds_input").val(txt);
}
txt = txt.toString();
if (txt.indexOf('.') > -1) {
if (txt.substr(txt.indexOf('.') + 1, txt.length).length > 1) {
txt = txt.substr(0, txt.length - 1);
$("#tds_input").val(txt);
}
}
}

Using type=number (and not text) can help
function validatePercent(event)
{
var txt=$("#tds_input").val();
if(!parseInt(txt))
{
$("#tds_input").val('');
}
if(isNaN(txt/1))
{
txt=txt.substr(0,txt.length-1);
$("#tds_input").val(txt);
}
if(txt>100)
{
txt=txt.toString();
txt=txt.substr(0,txt.length-1);
$("#tds_input").val(txt);
}
txt=txt.toString();
if(txt.indexOf('.')>-1)
{
if(txt.substr(txt.indexOf('.')+1,txt.length).length>1){
txt=txt.substr(0,txt.length-1);
$("#tds_input").val(txt);
}
}
}
input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
-webkit-appearance: none;
margin: 0;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="number" id = "tds_input" onkeyup="validatePercent()">

UPDATED
You could store the value of the when the focus is in the input.
When the user enters a valid percentage (integer only), replace the value stored. When inputs is incorrect, just replace with the old value.
var decimalSeparator = 1.1.toLocaleString().replace(/\d/g, ''),
pattern1 = "^(\\d{1,3})?([",
pattern2 = "]?\\d{1})?$",
regex = new RegExp(pattern1+decimalSeparator+pattern2),
resetContent = function () {
$('#tds_input').val($('#tds_input').data('val'));
},
matchRegex = function (value) {
return value.match(regex);
};
$('#tds_input').bind('focusin', (e) => {
$('#tds_input').data('val', $('#tds_input').val());
});
// handle input (keys, paste)
$('#tds_input').bind('input', (e) => {
let txtValue = $('#tds_input').val();
// input is empty
if (txtValue === "") {
$('#tds_input').data('val', "");
return;
}
// value does not match regex
if (!matchRegex(txtValue)) {
// maybe it ends with the decimal character?
if (txtValue[txtValue.length - 1] === "." && txtValue !== "100.") {
// simulate the user enters a decimal next
if (matchRegex(txtValue + "1")) {
$('#tds_input').data('val', txtValue);
return;
}
}
resetContent();
return;
}
// check between 0 and 100
let value = parseFloat(txtValue);
if (value >= 0 && value <= 100) {
// store new valid number
$('#tds_input').data('val', value);
// put the value as an integer in the input
$('#tds_input').val(value);
return;
} else resetContent();
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" id="tds_input"/>

How to Validate Text box on depend of another Text box?

I am Performing Calculation of Student fee Details,There are Two Text boxes,one which is automatically fixed(disabled)as Rs.5000,If i enter value below Rs.5000 value on another Text box then it will calculate subtraction and show balance in result text box.If i enter value above Rs.5000 it should not take that value in second text box.I want to validate text box depending on first text box value.
Here is my body part
my script part
$(".maxmin").each(function () {
var thisJ = $(this);
var max = thisJ.attr("max") * 1;
var min = thisJ.attr("min") * 1;
var intOnly = String(thisJ.attr("intOnly")).toLowerCase() == "true";
var test = function (str) {
return str == "" || /* (!intOnly && str == ".") || */
($.isNumeric(str) && str * 1 <= max && str * 1 >= min &&
(!intOnly || str.indexOf(".") == -1) && str.match(/^0\d/) == null);
// commented out code would allow entries like ".7"
};
thisJ.keydown(function () {
var str = thisJ.val();
if (test(str)) thisJ.data("dwnval", str);
});
thisJ.keyup(function () {
var str = thisJ.val();
if (!test(str)) thisJ.val(thisJ.data("dwnval"));
})
});

You can do on textchanged something like this
$(textbox1).on('change', function () {
if(textbox1.val()==5000){
//do your code
}
else if(textbox1.val()<5000){
//do your code
}
});

Look into the onchange (https://api.jquery.com/change/) or keyup events (https://api.jquery.com/keyup/). Get the values and perform your calculations.

comma format as typing in angular

In jqxwidget
http://www.jqwidgets.com/jquery-widgets-demo/demos/jqxnumberinput/index.htm
by default the comma’s are already in place and separated by underscore.
what i want is to have the field empty and as soon as user starts typing the comma should come as and when similarly to F2 cell render-er.
so when typed 100 is should show 100
when typed 10000 ,it should show 10,000
also i have angular in my app as we are using jqxwidget in conjucation with so any angular way is also fine
one plugin i have found does the job but when focus out not when typing
https://www.npmjs.com/package/angular-numeric-directive

Hey I have solved this before by creating a directive that applies a filter to your HTML input. Here is a jsfiddle example
This is the directive. It both formats the user's input and keeps the cursor where the user is typing. My one issue with this is the logic behind where the cursor should be pointed.
fessmodule.directive('format', ['$filter', function ($filter) {
return {
require: '?ngModel',
link: function (scope, elem, attrs, ctrl) {
if (!ctrl) return;
var parts = attrs.format.split(':');
attrs.foramtType = parts[0];
attrs.pass = parts[1];
ctrl.$formatters.unshift(function (a) {
return $filter(attrs.foramtType)(ctrl.$modelValue, attrs.pass)
});
ctrl.$parsers.unshift(function (viewValue) {
var cursorPointer = elem.context.selectionStart;
var plainNumber = viewValue.replace(/[^\d|\-+|\.+]/g, '');
elem.val($filter(attrs.foramtType)(plainNumber, attrs.pass));
elem.context.setSelectionRange(cursorPointer, cursorPointer);
return plainNumber;
});
}
};
And the HTML to activate it
<input type="text" ng-model="test" format="number:2" />

Angular already provides pretty basic formatting filters
like
html : {{val | number:0}}
script: $scope.val = 1234.56789;
ref:
https://docs.angularjs.org/api/ng/filter/number
https://docs.angularjs.org/api/ng/filter/currency
https://scotch.io/tutorials/all-about-the-built-in-angularjs-filters

Demo
<input value="100000000" id="testInput" />
Simply apply this .formatInput(numberOfCharactersForSeparator, Separator ); to your input
$(document).ready(function()
{
$("#testInput").formatInput(3,"," );
});
using this plugin that i just made :p
$.fn.formatInput = (function(afterHowManyCharacter,commaType)
{
if(afterHowManyCharacter && commaType != ".")
{
var str = $(this).val();
var comma = commaType != undefined ? commaType : "," ;
var strMod ;
if($(this).val().indexOf(".") == -1)
strMod = replaceAll(comma,"",$(this).val());
else
{
strMod = replaceAll(comma,"",$(this).val());
strMod = strMod.substring(0,strMod.indexOf("."));
}
if($(this).val().indexOf(".") != -1)
$(this).val(splitByLength(strMod,afterHowManyCharacter).join( comma )+ $(this).val().substring($(this).val().indexOf(".")));
else
$(this).val(splitByLength(strMod,afterHowManyCharacter).join( comma ));
var nowPos = 0;
$(this).on("keyup",function(e)
{
nowPos = doGetCaretPosition($(this)[0]);
var codePressed = e.which ;
if(" 8 37 38 39 40 46 17".indexOf(" "+codePressed) == -1 && !e.ctrlKey)
{
if($(this).val().length >afterHowManyCharacter)
{
strMod ;
if($(this).val().indexOf(".") == -1)
strMod = replaceAll(comma,"",$(this).val());
else
{
strMod = replaceAll(comma,"",$(this).val());
strMod = strMod.substring(0,strMod.indexOf("."));
}
if($(this).val().indexOf(".") != -1)
$(this).val(splitByLength(strMod,afterHowManyCharacter).join( comma )+ $(this).val().substring($(this).val().indexOf(".")));
else
$(this).val(splitByLength(strMod,afterHowManyCharacter).join( comma ));
if((strMod.length-1)%afterHowManyCharacter == 0)
{
setCursor($(this)[0],nowPos+1);
}
else
{
setCursor($(this)[0],nowPos);
}
}
}
});
}
else if( commaType == ".")
{
console.log("You can't use . as Separator");
}
function splitByLength(str,maxLength)
{
var reg = new RegExp(".{1,"+maxLength+"}","g"); ;
return reverseStringInArray(str.split("").reverse().join("").match(reg).reverse());
}
function replaceAll(find, replace, str) {
return str.replace(new RegExp(find, 'g'), replace);
}
function reverseStringInArray(arr)
{
$.each(arr,function(i,val)
{
arr[i] = arr[i].split("").reverse().join("");
});
return arr ;
}
// Author of setCursor is nemisj
function setCursor(node,pos)
{
node = (typeof node == "string" || node instanceof String) ? document.getElementById(node) : node;
if(!node){
return false;
}else if(node.createTextRange){
var textRange = node.createTextRange();
textRange.collapse(true);
textRange.moveEnd(pos);
textRange.moveStart(pos);
textRange.select();
return true;
}else if(node.setSelectionRange){
node.setSelectionRange(pos,pos);
return true;
}
return false;
}
// Author of setCursor is bezmax
function doGetCaretPosition (oField) {
// Initialize
var iCaretPos = 0;
// IE Support
if (document.selection) {
// Set focus on the element
oField.focus ();
// To get cursor position, get empty selection range
var oSel = document.selection.createRange ();
// Move selection start to 0 position
oSel.moveStart ('character', -oField.value.length);
// The caret position is selection length
iCaretPos = oSel.text.length;
}
// Firefox support
else if (oField.selectionStart || oField.selectionStart == '0')
iCaretPos = oField.selectionStart;
// Return results
return (iCaretPos);
}
});

<html>
<script src= "http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script>
<script>
var app = angular.module('app',[]);
app.controller('myCtrl',function($scope){
$scope.name = "1232.33";
$scope.changeFormat = function(value){
$scope.name = Number(value).toLocaleString('en');
}
});
</script>
<body>
<div ng-app="app" ng-controller="myCtrl">
<p>Input something in the input box:</p>
<p>Number: <input type="text" ng-model="name" placeholder="Enter name here" ng-blur="changeFormat(name)"></p>
<h1>Formatted value {{name}}</h1>
</div>
</body>
</html>

Here is a hackish solution. The idea is to watch for changes in the input text and format the input accordingly.
HTML
<div ng-controller="so">
<input ng-model="salary"></input>
</div>
Javascript
app.controller('so', function($scope) {
$scope.salary = '12567';
$scope.$watch('salary', function(){
// strip out all the commas and dots
var temp = $scope.salary;
if (!temp) return; // ignore empty input box
var lastChar = temp[temp.length-1];
if (lastChar === ',' || lastChar === '.') // skip it/allow commas
return;
var a = temp.replace(/,/g,''); //remove all commas
//console.log(a);
if (isNaN(a))
$scope.salary = temp.substring(0, temp.length-1); // last char was not right
else {
var n = parseInt(a, 10); // the integer part
var f = ''; // decimal part
if (a.indexOf('.') >= 0) // decimal present{
if (lastChar === '0') // 0's after decimal point are OK
return;
f = ('' + parseFloat(a)).substr(a.indexOf('.'));
}
var formatted_salary = '';
var count = 0;
var ns = '' + n; // string of integer part
for (var i=ns.length-1; i>=0; i--) {
if (count%3===0 && count>0)
formatted_salary = ',' + formatted_salary;
formatted_salary = ns[i] + formatted_salary;
count += 1;
}
formatted_salary = formatted_salary + (f ? f : '');
$scope.salary = formatted_salary;
}
})
})
Here is the JSFiddle
It gracefully handles things like
won't allow any characters other than numbers , and .
multiple commas and dots formatted correctly
PS:- you might want to handle the proper positioning of the caret yourself using text range. I haven't included that here.

100 => 100
1000 =>1,000
10000 => 10,000
100000 => 100,000
...
10000000 => 10,000,000
10000000.540 => 10,000,000.540
I use ng-change event to make this example
// on-change event
$scope.ngchanged = function (val) {
$scope.iputval = numberWithCommas(val);
};
function numberWithCommas(n) {
while (n.toString().indexOf(",") != -1)
{
n = n.replace(",", "");
}
var parts = n.toString().split(".");
return parts[0].replace(/\B(?=(?:\d{3})+(?!\d))/g, ",") + (parts[1] ? "." + parts[1] : "");
}
Use it
<input type="text" ng-model="iputval" ng-change="ngchanged(iputval)" />
Updated add demo and code by following link
Full code and demo >> here

Please check out ng-number-input
I think it accomplishes the task easily.
https://www.npmjs.com/package/ng-number-input
I made it for my project and I thought I'd share it with the community.
Source code available on git hub and link is available in npm page.

Jquery keydown() with number format not work correctly on android webview

I have encountered a strange behavior on android browser / webview. I was testing an input that will automatically format to phone number format "(xxx) xxx-xxxx". But then what happened was when I tapped or press any number on androids keyboard, the first input was like this "(x" but then the cursor was in between "(" and "x". Is there a way to put the cursor after "x" value?
I tested this on iPhone and windows web browsers and it works fine. Please let me know if there are mistakes on my jquery or javascripts.
Thanks
HTML CODE:
<html>
<head>
<title>Sample Phone Number Format</title>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.8.2.min.js"></script>
</head>
<body>
<input type="text" id="phone" />
<script type="text/javascript">
$('#phone').on('keydown', function (event) {
objval = $(this).val();
if (event.keyCode == 46 || event.keyCode == 8) {} else {
if (!((event.keyCode > 47 && event.keyCode < 58) || (event.keyCode > 95 && event.keyCode < 106) || (objval.length > 13))) {
event.preventDefault();
} else {
if (objval.length == 0) {
$(this).val(objval + '(');
alert(objval + '(');
} else if (objval.length == 4) {
$(this).val(objval + ') ');
alert(objval + ') ');
} else if (objval.length == 9) {
$(this).val(objval + '-');
alert(objval + '-');
} else if (objval.length >= 14) {
if (event.keyCode == 9) {
return;
} else {
event.preventDefault();
}
}
}
}
});
$('#phone').on('keydown', function (event) {
var objVal = $(this).val();
if(objVal.length < 14)
{
validateCallerForm(objVal + String.fromCharCode((96 <= event.keyCode && event.keyCode <= 105)? event.keyCode-48 : event.keyCode));
}
});
//Validates proper phone format, true if valid phone number, false otherwise
function isValidPhoneNumber(elementValue) {
var numberPattern = /^\(?(\d{3})\)?[- ]?(\d{3})[- ]?(\d{4})$/;
return numberPattern.test(elementValue);
}
//validates entire caller form, also updates css classes for proper response
function validateCallerForm(PhoneNumber) {
if (isValidPhoneNumber(PhoneNumber)) {
alert("true");
} else {
alert("false");
}
}
</script>
</body>
</html>
Giving +50 Bounty to who'm will answer this correctly

you have to first define listener for typing and copy-paste like below (not required) :
$("#phone").keyup( function() {
maskLine(this);
});
$("#phone").change( function() {
maskLine(this);
});
Then, to manage cursor placement, you have to cache previous phone number and then, you could compare difference and update cursor position if needed.
So declare, you have to declare a global array like this :
var _cacheElementValues = new Array();
At last, you can check the function below, it applies your mask to phone number field and manage cursor placement :
function maskLine( element ) {
element = $(element);
var maskedLine = '';
var line = element.attr('value');
// check the cache of the input and abord if no change since last treatment
if (_cacheElementValues[element.attr('id')] != undefined && _cacheElementValues[element.attr('id')] == line) {
return;
}
line = line.replace(/\D/g, ''); // remove all characters != digits
line = line.substring(0, 10);
if (line != '') {
// apply mask
if (line.length <= 2 ) {
maskedLine = "(" + line;
} else if (line.length < 6) {
maskedLine = line.replace(/^([0-9]{3})([0-9]{0,3})/g, '($1) $2');
} else {
// mask : '(XXX) XXX-XXXX'
maskedLine = line.replace(/^([0-9]{3})([0-9]{3})([0-9]{0,4})/g, '($1) $2-$3');
}
}
// define cursor position at the end of the input by default
var pos = maskedLine.length;
// Change cursor placement if necessary
if (typeof element[0].selectionStart != 'undefined') {
var start = element[0].selectionStart;
var end = element[0].selectionEnd;
var insText = element[0].value.substring(start, end);
// get current cursor placement
if (insText.length == 0) {
pos = start;
} else {
pos = start + insText.length;
}
// find how many digits typing since last mask application
var previousLength = 0;
if (_cacheElementValues[element.attr('id')] != undefined) {
previousLength = _cacheElementValues[element.attr('id')].replace(/\s/g, '').length;
}
var diff = maskedLine.replace(/\s/g, '').length - previousLength;
// if sum of new typing digit is > 0 : we change cursor placement
if (diff > 0) {
pos += (diff - 1) + Math.round((diff-1)/3);
if (pos%6 == 0 && maskedLine.length >= pos+1) pos++;
}
}
// update input data & cache
element.val(maskedLine);
_cacheElementValues[element.attr('id')] = maskedLine;
// update cursor placement
element[0].selectionStart = element[0].selectionEnd = pos;
}
You can find this example on jsFiddle : http://jsfiddle.net/UE9LB/5/
I hope this little explantion can solve your problem ;)
Enjoy !
ps: i apologize for my poor english :s

I'd recommend at least starting with an existing plugin rather than going through your own isolated rounds of solving issues.
http://digitalbush.com/projects/masked-input-plugin/
https://github.com/igorescobar/jQuery-Mask-Plugin

The short answer is to set the selectionStart and selectionEnd properties of the input element. After you format the value, set these properties to this.value.length.
this.selectionStart = this.value.length;
this.selectionEnd = this.value.length;
But, where you are going to run into trouble is when the cursor is not at the end of the text. Eg, the user has manually positioned the cursor to a position within the text. To prevent the cursor from jumping to the end, you will need to detect the cursor position before you format the input, then put the cursor back in the appropriate position after formatting.
Edit: This jsFiddle may get you started, but isn't perfect yet.

I rewrite the code on my #phone keydown event and this will work on iPhone, Android, webkit browsers.
$('#phone').on('keydown', function (event) {
if (event.keyCode == 8 || event.keyCode == 37 || event.keyCode == 39) {
// ignore if BKSPCE, left arrow, or right arrow
} else {
// validate if anything else
inputval = $(this).val();
var string = inputval.replace(/[^0-9]/g, "");
var first3 = string.substring(0,3);
var next3 = string.substring(3,6);
var next4 = string.substring(6,10);
var string = ("(" + first3 + ") " + next3 + "-" + next4);
$(this).val(string);
}
});

Can't get JavaScript to check for null objects

I really don't know what the issue is here. As far as I can see, the code is simple and should work fine.
var Prices="";
for (var PriceCount = 1; PriceCount <= 120; PriceCount++) {
var CurrentPrice = "Price" + PriceCount;
if (prevDoc.getElementById(CurrentPrice).value != null) {
if (Prices == "") {
Prices = prevDoc.getElementById(CurrentPrice).value;
} else {
Prices += "," + prevDoc.getElementById(CurrentPrice).value;
}
} else {
break;
}
}
There could be up to 120 hidden inputs on the form. The moment we check for an input that doesn't exist the loop should break. My test page has two input elements that get pulled. On the third (the null) I get this error in firebug:
prevDoc.getElementById(CurrentPrice) is null
if (prevDoc.getElementById(CurrentPrice).value != null) {
Yes it is null...that's what the check is for ಠ_ಠ
Does any one know what I'm doing wrong? This seems like it should be really straight forward.
EDIT:
for clarity's sake, prevDoc=window.opener.document

if (prevDoc.getElementById(CurrentPrice).value != null) {
can be expanded to:
var element = prevDoc.getElementById(CurrentPrice);
var value = element.value; /* element is null, but you're accessing .value */
if (value != null) {

value is never null.
If it is not filled in, the value would be "" or a length of zero.
If the element does not exist, you would check for the existence of the element.
var CurrentPrice = "Price" + PriceCount;
var elem = prevDoc.getElementById(CurrentPrice);
if (elem && elem.value != null) {

I think it should be:
var Prices="";
for (var PriceCount = 1; PriceCount <= 120; PriceCount++) {
var CurrentPriceId = "Price" + PriceCount,
CurrentPrice = prevDoc.getElementById(CurrentPriceId);
if (CurrentPrice != null) {
Prices = (Prices == "") ? CurrentPrice.value : (Prices + "," + CurrentPrice.value);
}
else break;
}

Try
if (prevDoc.getElementById(CurrentPrice) !== null)