JavaScript Coder

javascript form validation

How to Use the Dreamweaver Form Validation Feature

Sometimes, you may feel frustrated when you look at the form submissions that you get from a web form and find out that the respondents did not fill in some crucial details. This calls for some details on the form to become mandatory to fill in. for example, a form that is used to subscribe visitors to regular newsletters via email will be of no use if the user does not enter their email address.

Continue Reading →

JavaScript Form Validation : quick and easy!

Using client side JavaScript is an efficient way to validate the user input in web forms. When there are many fields in the form, the JavaScript validation becomes too complex. The JavaScript class presented here makes the form validations many times easier. Contents Download the JavaScript form validation script Using the form validation script Adding a custom validation Table of Validation Descriptors

Continue Reading →

JavaScript Form Validation Script: More features

This is in continuation of the JavaScript Form Validation script in this page. In this page, we will see some of the advanced features of the script. Showing all the form validation errors together in a message box If you want to show all the error messages together, then just call the EnableMsgsTogether() function as shown below. frmvalidator.EnableMsgsTogether(); See the form validation demo Showing the form validation errors on the page itself You can display the validation errors on the page itself.

Continue Reading →

Simfatic Forms Validation: save your time coding

This is in continuation of the JavaScript form validation script explained here. Simfatic Forms is a complete web form development software. You can create forms add form validations, select your options for server side processing, generate the script and install the form on the web server. No coding required. This page takes you through some of the form validation features of Simfatic Forms. Add validations to your existing forms You can choose to create a new fresh form or read the form from an existing web page.

Continue Reading →

Javascript code to validate email addresses

Validating email address in put using Javascript can be tricky. Contrary to popular belief, email addresses can contain almost all type of characters and a valid email address can take complex forms. For example, the email addresses below are perfectly valid: firstname+lastname@domain.com much.”more\ unusual”@example.com あいうえお@a.long.domain.example.university One of the straight forward way to validate an email address is using regular expressions Here is a moderately reasonable email validation function using regular expression:

Continue Reading →

JavaScript Form Validation - Confirm Password

Here is a quick JavaScript validation to check whether password and confirm password fields match. The code below compares the field( password and confirm password) values and displays the error message when the passwords does not match. Sample Javascript code for comparing password with confirm password function validateForm(event) { var password = document.getElementById('myform_password').value; var conf_password = document.getElementById('myform_confirm_password').value; if (password && password !== conf_password) { document.getElementById('error_pswd_match').classList.remove('hidden'); } else { document.getElementById('error_pswd_match').classList.add('hidden'); alert("Validation Success!

Continue Reading →

JavaScript Form Validation - Date

It may be tempting to validate date input using regular expressions. However, the better alternative will be to actually convert the date to a date object and test it. For example, a simple regular expression test would approve this date: 2011/02/29 perfectly valid but there is no such date (since 2011 was not a leap year) Validate dates in the format: MM/DD/YYYY (or MM-DD-YYYY or MM.DD.YYYY ) function validateDate_MMDDYYYY(input_date) { var parts = input_date.

Continue Reading →

JavaScript Form Validation - Phone Numbers

The easiest way to validate phone numbers using Javascript would be to use Regular expressions. However there are different formats of Phone numbers depending on the user's preference. Here are some regular expressions to validate phone numbers Phone number validation using a simple Regular expression function validatePhoneNumber(input_str) { var re = /^[\+]?[(]?[0-9]{3}[)]?[-\s\.]?[0-9]{3}[-\s\.]?[0-9]{4,6}$/im; return re.test(input_str); } This function will allow phone numbers entered in the formats like this (123) 456-7890 (123)456-7890 123-456-7890 1234567890 Try the working demo See the Pen eYmbjpG by Prasanth (@prasanthmj) on CodePen.

Continue Reading →

Javascript password validation alphanumeric string

In case you want to allow only alpha-numeric characters in your password, here is the validation to check that condition: Alpha-numeric regular expression test Here is the function to test whether the inut matches an alphanumeric pattern: function validateAlphaNumericPassword(pwd) { var re = /^[a-z0-9]+$/i return re.test(pwd) } Alphanumeric with hyphen Sometimes, you may want to allow some characters like hyphen ( - ) in addition to alpha-numeric characters. Here is the validation

Continue Reading →

Javascript password validation using regular expression

Suppose you want to validate whether the password has at least one number other than alphabetic characters. Here is the regular expression to validate that condition Check at least one number exists in the password Here is the regular expression validation that confirms at least one number exists in the password function validatePassword(pwd) { var re = /^(?=.*\d).+$/ return re.test(pwd) } This regular expression makes use of (positive lookahead assertion)[https://stackoverflow.com/a/1570916/1198745] (?

Continue Reading →

Javascript validation simple example code

Here is a simple form validation code that validates a simple form No additional library is used. It is pure Javascript First step - add an event listner for form submit event Here is the code that does that step: document.getElementById('myform').addEventListener('submit', validateForm); function validateForm() { } First, we get the form DOM object using the ID attribute of the form. Then we listen to the form submit event. Next, we have to validate each of the fields in the form.

Continue Reading →

The Most Indispensable jQuery Form Validation Reference Guide

Using a library to do form validation can save lots of your development time. Being a tested and proven library guarantees it. jQuery Form validation library is the most popular validation library. This post collects all my notes and references on jQuery Form validation library. This includes a large bunch of sample code and a complete reference guide to all the built-in validation rules in the library. Reference Links: Website: http://jqueryvalidation.

Continue Reading →