Javascript form input text length

Count and display number of characters in a textbox using Javascript

I am working on a project that requires me to count the number of characters entered in a text box and dynamically display the result elsewhere on the page. As I said, this would preferably be done in jQuery or Javascript. Thanks in advance.

6 Answers 6

You could do this in jQuery (since you said you preferred it), assuming you want the character count displayed in a div with :

$('textarea').keyup(updateCount); $('textarea').keydown(updateCount); function updateCount()

UPDATE 2: Updating to include keydown for long presses.

 function countChars(countfrom,displayto) 
0 characters entered. 

Plain Javascript.

This is correct but I want to note that it’s better to use .textContent instead of .innerHTML if you’re adding text content to an element since innerHTML parses data as HTML while .textContent uses straight text which is faster.

$('textarea').keyup(updateCount); $('textarea').keydown(updateCount); function updateCount()

I would like to share my answer which i used in my project and it is working fine.

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Get Input Value Length in JavaScript

In this tutorial we will learn how to Get Input Value Length in JavaScript. HTML DOM getElementById() method, JavaScript length property and JavaScript value property is used for this purpose.

HTML Code

HTML Code is given below, in this code we have a input tag and a button tag with onclick event which will execute a JavaScript function to get the length of the value inside the input element.

JavaScript Code

Take a look at the JavaScript code, the HTML Dom getElementById() method, length property and value property is used.

getElementById() Method

getElementById() Method is used to select element with the specified id.

JavaScript value property

JavaScript value property is used to set or get the value of the selected HTML element.

JavaScript length property

JavaScript length property is used to get the length of the string. In this example it will return the length of the value of input element.

Demo

Video Tutorial

Watch video tutorial on Get Input Value Length in JavaScript.

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How to check string length with JavaScript

I want to get the string length when a key is pressed like StackOverflow does. I have tried to do this with onblur , but it’s not working. How do I do this?

onblur refers to the opposite of focus, i.e. you are leaving the field. This is not the appropriate event handler.

11 Answers 11

Here’s an example, DOM0-style:

someElement.oninput = function() < this.onkeydown = null; // Your code goes here >; someElement.onkeydown = function() < // Your code goes here >; 

The other question is how to count the number of characters in the string. Depending on your definition of “character”, all answers posted so far are incorrect. The string.length answer is only reliable when you’re certain that only BMP Unicode symbols will be entered. For example, ‘a’.length == 1 , as you’d expect.

However, for supplementary (non-BMP) symbols, things are a bit different. For example, ‘𝌆’.length == 2 , even though there’s only one Unicode symbol there. This is because JavaScript exposes UCS-2 code units as “characters”.

Luckily, it’s still possible to count the number of Unicode symbols in a JavaScript string through some hackery. You could use Punycode.js’s utility functions to convert between UCS-2 strings and Unicode code points for this:

// `String.length` replacement that only counts full Unicode characters punycode.ucs2.decode('a').length; // 1 punycode.ucs2.decode('𝌆').length; // 1 (note that `'𝌆'.length == 2`!) 

P.S. I just noticed the counter script that Stack Overflow uses gets this wrong. Try entering 𝌆 , and you’ll see that it (incorrectly) counts as two characters.

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How to get length in Javascript of an array of Form text fields

Note that, strictly speaking, your input elements do not constitute an array. They’re nodes in the DOM, so you have to find them as an array.

I know you said «no jQuery», but in this day and age it really perplexes me when people are resistant to using tools like that. They solve lots of problems that you’ll otherwise end up solving yourself.

I would be shocked to learn that it has no getElementById() support. Now, it’s probably broken like it is in regular IE (it returns elements based on the «name» attribute sometimes), but it would be pretty weird for it to be missing completely. Then again, assuming Microsoft wouldn’t do something weird like that is probably a bad idea.

:headslap: I don’t think my teeth could stand the grinding if I were an MS Mobile developer — you have my admiration.

    
 
Java script to calculate price with the double dimension arrays
 
origional script modified by amarjit lehal :lehal2@hotmail.com
 
Item
 
Description
 
Price
 
Total
 
 
 
Item1!
 
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Item2
 
$ 
 
Item3
 
$ 
 
Item4
 
$ 
 
 
Order Total 
 
 
 
 
Discount 
 
 
 
 
Grand Total 
 
 
 

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