Develop Reference

regex to replace non numeric

I want to replace all my non numeric characters with an empty string. I found this solution
I am trying to replace the value of an input element on change. But when I use above, it is not replacing until I press a number.
Each non-digit I type stays until I type a digit
Ex: 2aaaaa will not be replaced. But as soon as 2aaaa3 is typed it will replace all the a's and it becomes 23
Is this the normal behaviour? How can I achieve my requirement.
component.ts
mobileChanged = () => {
this.mobile = this.mobile.replace(/\D/g,'');
};
angular component.html
<input type="text" [(ngModel)]="mobile" (ngModelChange)="mobileChanged()">

You can use keyup from jQuery or onkeyup from Javascript.
$("document").ready(function() {
$("input").keyup(function() {
let v = this.value.replace(/\D/g, '');
this.value = v;
})
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="text" value="" />

Yes, it's the usual behaviour for ngModelChange but seems you need onkeyup event here to replace Non-digits. Something like-
function mobileChanged() {
var txtinput = document.getElementById("fname");
var x = txtinput.value.replace(/\D/g,'');
txtinput.value = x;
}
<input id ="fname" type='text' onkeyup="mobileChanged()">
See if you still have confusion: https://stackoverflow.com/a/46403258/1138192

compare Two field if the field is in the content of other field using javascript after submit button clicked

Hi I am not a javascript expert thats why I will really appreciate any advice
I have a textfield named try where in I will input something
ex:
try value is
87
then I have another textfield named field11
field11 has a value of
777-a98;87-bx23;000-t88;245-k7
I wanted to compare try and field11 if try is found in the content of field 11 it will set the textfield named msg to 87-bx23 matched
msg value will be
87-bx23 matched
my code is like this but its not giving the desired output I know my comparison is wrong it just I dont know how
<script>
$(document).ready( function(){
$('#submit').click(function() {
if (document.getElementById('try').value != document.getElementById('field11').value)
{
alert('dont match!');
$("#msg").val ("dont match!");
}
else if (document.getElementById('try').value == document.getElementById('field11').value) {
}alert(document.getElementById('try').value + " exists");
$("#msg").val(document.getElementById('try').value + " exists");
});
});
</script>
I also try this but if I input 77 it saying it exist even not
<div id="requirement #2">
<button type="button" id="button2" onclick="StringSearch()">Search</button>
</div>
<script>
function StringSearch() {
var SearchTerm = document.getElementById('try').value;
var TextSearch = document.getElementById('field11').value;
if (SearchTerm.length > 0 && TextSearch.indexOf(SearchTerm) > -1) {
alert("Patient Exists");
} else {
alert("Patient Does not exist click add if you want to add the patient");
$("#msg").val(document.getElementById('try').value + " exists");
$("#t1").val("1");
}
}
</script>

document.getElementById('field11').value.match(new RegExp("(" + "87" + "-[a-z0-9]+);"))[1])
The Generated Regex when try value = 87:
/(87-[a-z0-9]+);/
So what is this monstrosity? We generate a Regex Expression, that looks for the try value followed by a dash, and one or more characters from a-z or 1-9, followed by a semicolon. String.match() is used to determine an array of matches, the array[1] is the first capture group (the part of the RegEx between the brackets), which is in this case 87-bx23

I have tried to rewrite your code to store variables for the elements and use a Regexp to do the search for the value:
<script>
$(document).ready( function(){
var tryElem = document.getElementById('try');
var field1 = document.getElementById('field11');
$('#submit').click(function() {
var regex = new Regexp(tryelem +'[^;]*');
var match = regex.exec(field.value);
if (match)
{
alert(match + " exists");
$("#mag").val(match + " exists");
}
else
{
alert('dont match!');
$("#msg").val ("dont match!");
}
});
});
</script>
The code does more or less the same as yours, except for the regex:
tryelem +'[^;]*'
It builds a regular expression form the the value of tryElem and then it searches forward and matches up to the first semi colon (zero or more characters).
Now the match will contain: '87-bx23'.

You can try this:
<input type="text" id="try"/>
<input type="text" id="field11" value="777-a98;87-bx23;000-t88;245-k7"/>
<input type="text" id="msg"/>
<input type="button" id="submit"/>
And js:
$(function(){
$("#submit").click(function(){
var Try=$("#try").val(),
f11=$("#field11").val(),
msg=$("#msg");
//but if you want search in number part only (before dash sign), uncomment line below and comment next line.
//var r=((";"+f11+";").match(new RegExp(";([^;-]*"+Try+".*?-.+?);"))||[])[1];
var r=((";"+f11+";").match(new RegExp(";([^;]*"+Try+"[^;]*);"))||[])[1];
msg.val(r||"don't match!!");
});
});
You can check or change both of them online

How to check if a string contain a list if characters which are not in english

I want to valid textbox text. the textbox is for a phone number so, of course, letters and anything other the number I used different kinds of code
ex
$(document).ready(function () {
$("#sub").click(function () {
var regex = /[$%^&*()_+[]{}<>?]אבגדהוזחטיכךלמםנןסעפצקרשת \"/
var bleangth = $('.bphone').val().length;
var eleangth = $('.ephone').val().leangth;
var cbphone = $('.bphone').val();
var cephone = $('.ephone').val();
if (bleangth < 3 || eleangth < 7) {
$('#bad').removeClass("error");
$('#short').addClass("error");
}
else
if (regex.test(cbphone) || regex.test(cephone)) {
$('#short').removeClass("error");
$('#bad').addClass("error");
}
else {
$('#bad').removeClass("error");
$('#short').removeClass("error");
//$('h3').removeClass("snerror")
}
alert( "end " + regex.test(cephone) +" start " + regex.test(cbphone));
});
As you see I entered letters from different language but for some reason the code can't "read" it and return true is there a way maybe to get string split it to array and then use it? or different code or something I need to add/ download
Thank you in advance

You can make regular expression with unicode value
var regex = /^[\u05d0-\u05ea]|[$%^&*()_+{}<>\]\[?]$/
Example
$(document).ready(function(){
var regex = /^[\u05d0-\u05ea]|[$%^&*()_+{}<>\]\[?]$/
$("#buttonCheck").click(function(){
alert(regex.test($("#text").val()));
});
});
Example Link

If requirement is for only numbers to be input you should be able to use NOT operator ! operator with RegExp /\D/ ; e.g.; !/\D/.test(/*input*/) where true would be result if input is a digit, false if input is not a digit.
An approach using HTML5 <input> element with pattern attribute set to \d+, required attribute; <label> element, CSS :focus, :invalid , adjacent siblings selector +
input + label {
display:none;
}
input:focus:invalid + label {
display:block;
color:red;
}
<input type="text"
pattern="\d+"
placeholder="Please input digits 0-9"
required /><label>Invalid input. Please input digits 0-9</label>

How do I allow the user to only input a string?

function EnterCandidates() {
var candidateNameInputs = document.querySelectorAll('input[id^=C]'),
names = document.querySelectorAll('label[for^=V][id^=L_V]');
Array.prototype.forEach.call(names, function(label, index) {
if (candidateNameInputs[index].value !== candidateNameInputs[index].defaultValue) {
label.textContent = candidateNameInputs[index].value;
}
});
}
I have this code which gets the users input and changes the label with it but i want to add some code which only allows the user to enter letters of the alphabet. How would I go about this using this code?

If you are using modern browsers then user html5 validation -
<input type="text" name="name" class="field" pattern="[a-zA-Z ]+" />
It accepts a-z and A-Z plus space

listen to keyDown event and match with this regex:
/[a-zA-Z]+/
if you're targeting modern browsers only, you can try this:
<input type="text" pattern="[a-zA-Z]" title="Only letters" />

you can't avoid that the user types non alphabetic characters. But you can:
- control the input fields (onkeydown) and check if there are some characters you don't want Stackoverflow - force input to only alpha-letters
- do the same before the
label.textContent = candidateNameInputs[index].value;
line and filter/replace the characters you don't want

var val = document.getElementById('id').value;
if (!val.match(/^[a-zA-Z]+$/))
{
alert('Only alphabets are allowed');
return false;
}
full script
function EnterCandidates() {
console.log('woo');
var candidateNameInputs = document.querySelectorAll('input[id^=C]'),
names = document.querySelectorAll('label[for^=V][id^=L_V]');
Array.prototype.forEach.call(names, function (label, index) {
if (!candidateNameInputs[index].value.match(/^[a-zA-Z]+$/))
{
alert('Only alphabets are allowed');
}
else
{
if (candidateNameInputs[index].value !== candidateNameInputs[index].defaultValue) {
label.textContent = candidateNameInputs[index].value;
}
}
});
}

Here is one way to do it using Javascript.
http://jsfiddle.net/q60gm0ra/
var input = document.getElementById('alpha');
input.addEventListener('keypress',function(e) {
var str = String.fromCharCode(e.charCode);
if (!(/[A-Z]|\s/i).test(str)) {
e.preventDefault();
}
});

Limiting input to a set of characters while also displaying those characters

I have seen in a few "username" fields where you type in a username, and below it, in something like a span, it will append it to a url. A lot like what is happening as I type this in StackOverflow at the bottom.
I would like to show only allowed characters from a list, ignore any input of characters not in that list.
I am really new to JS. In this case, I am using Jquery, and have a sort of works with some parts, and other parts I do not, or I have not gotten there yet.
Desire:
Input form field accepts only characters from a list, others are ignored.
Get the new key as entered, and append it to an element.
Here is the mess I have so far:
<script type="text/javascript" charset="utf-8">
$(document).ready(function() {
$('#cart-name').keyup(function(e) {
var entered = $('#cart-name').val();
entered = entered.toUpperCase();
var allowed = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_';
// fromCharCode always returns uppercase?
var entered_char = String.fromCharCode(e.which);
console.log('You entered: ' + entered_char);
var pos = allowed.indexOf(entered_char);
console.log('position is: ' + pos);
if (pos <= 0) {
console.log('does not contain');
} else {
console.log('contains');
}
$('#live').text(entered);
console.log(entered);
});
});
</script>
In the html I have:
<input type="text" name="cart_name" value="" id="cart-name" autocomplete="off" />
<br />
http://example.com/
<span id="live"></span>
<br />

Why not use a regular exprsession to replace non alphanumeric characters?
entered = entered.replace(/[^a-zA-Z 0-9]+/g,'');

Looking at your comments, you have some confusion over the different Key events:
keyup (and keydown) tell you which physical key has been pressed, while keypress will tell you which character has been typed - which is why you're always getting uppercase letters from fromCharCode.
I'm using something like this to sort out urls:
<script type="text/javascript" charset="utf-8">
$(document).ready(function() {
$('#cart-name').keypress(function(e) {
var entered = $('#cart-name').val();
// Regular Express to perform match on all alphanumeric characters,
// and - and _
var matchPattern = /[\w/_/-]/g;
var entered_char = String.fromCharCode(e.which);
console.log('You entered: ' + entered_char);
if (entered_char.match(matchPattern)) {
$('#live').text(entered + entered_char);
}
else if (enteredKey == " ") {
// Replace spaces with hyphens for SEO
$('#live').text(entered + "-");
}
});
});
</script>
Should see you right.