The purpose of a form validation script is to return a boolean value ('s to reference form fields, but that can lead to namespace conflicts and why make things more complicated than necessary.When the form is submitted - either by hitting Enter or clicking on the Submit button - the (the 'value' of the field called 'input' belonging to the form). In a real-life situation you will most likely have more fields to check, and more complicated conditions, but the principle remains the same.Server-side validation is more secure but often more tricky to code, whereas client-side (Java Script) validation is easier to do and quicker too (the browser doesn't have to connect to the server to validate the form, so the user finds out instantly if they've missed out that required field! In this tutorial we'll build a simple form with client-side Java Script validation.You can then adapt this form to your own requirements.
Each field in the form can have zero one or more validations. More info & downloads where Do My Validation One() and Do My Validation Two() are custom functions for validation.
This article assumes a general understanding of HTML and Java Script.
(16 printed pages) Introduction Getting Started Writing the Validation Script Connecting the Form to the Script Associating Form Fields with Custom Script Code Listing Conclusion When you create forms, providing form validation is useful to ensure that your customers enter valid and complete data.
Sometimes situations arise when a user should fill a single or more than one fields with alphabet characters (A-Z or a-z) in an HTML form.
You can write a Java Script form validation script to check whether the required field(s) in the HTML form contains only letters. To get a string contains only letters (both uppercase or lowercase) we use a regular expression (/^[A-Za-z] $/) which allows only letters.