Number Validation and Formatting using Javascript

• Download JSNumberFormatting - 1.77 KB

Introduction

The control uses javascript to handle number formatting as you keep typing and does the validation as well. For one of our requirement, we needed a javascript based control that did formatting as the users kept typing. Google search only yielded script that did formatting on focus change events only. So I went about creating a new control myself.

Background

The idea for this control came from one of our client requirement that needed a small javascript to have a textbox that will take big numbers. The numbers can have unlimited decimal places. Also the script will do 3 things at the same time.
1- It should only allow numbers (negative as well) and "." To be entered.
2- It should format the number as 1,234,567,789.123456789. It should execute such that the the commas are put while typing.
3- It should also only allow numbers that are as big as double can handle.

Using the code

Using the control is very easy and just needs adding the javascript code from the source page.

On the textbox on which the formatting needs to be applied, use the following code

onkeypress="return ValidateNumberKeyPress(this, event);" onkeyup="ValidateNumberKeyUp(this);"
onblur="ValidateAndFormatNumber(this)"

Points of Interest

Script is preety easy to read and understand. Some references that were used during the course of the script creation

• JavaScript Number Format Function