|
|
|
HTML Editors
So you want to create a web site? Great idea! There are few things in this world as satisfying as creating a good web site and having other people look at it, comment on it and like it. You have many choices in the tools that you use to perform...
Three Way Linking - Webmaster Strategy
Three way linking and concerns.
For many years SEO experts were happy with two way linking or reciprocal linking but in due time researchers anticipated a change in Search Engine’s Algo.
Not before too late it happened and the value of...
Tried and Tested Tips to Improve your Website - Part 1
1. DO NOT use excessive graphics or banner images on a single web page. They tend to slow the loading of your Web page. Impatient surfers might close their browser and move on. If you have many images on a single page, consider deleting few of...
Use CGI to Automate Your Web Site
Are you taking advantage of the powerful automation technology available on the Internet? Common Gateway Interface, better known as CGI, is one of the most widely used server applications on the Internet. This software resides on your server...
Using "Title Tags" With Your Web Links & Images
Using "Title Tags" for your web links & images is an arsenal many companies fail to utilize when planning out their web site optimization.
These tags will help search engines to navigate through your information.In the last topic we...
|
|
| |
|
|
|
|
|
|
Validating Numerical Input with JavaScript
What? Make a mistake entering data? Who me? NO WAY! Right…
Every form of data input by a user should be validated in some form or fashion. If you get
clean data in, you won’t get garbage out. This tutorial is going to explain how to validate
numerical data entered into a form using JavaScript.
First, let us begin with the code to insert the JavaScript into your HTML document.
Place these lines between the and tags.
This line tells the web browser to expect some JavaScript code and signal the beginning of
the script:
So now the format should look something like this:
My Title
Now on to validating the numerical input.
First we will create a function with one arument:
function validate(mydata){
These lines will test for a blank enty then prompt the user for input:
if (mydata == ""){
alert("Please enter a number.")
}
Next we will create a for loop which will look at each character in the data until it
reaches the end:
for(var i=0;i < mydata.length;i++){
Now create a variable and assign the
counter variable value to it:
var mydigit = mydata.charAt(i)
To screen out symbols, punctuation, and letters, place an if statement in the loop:
if(mydigit < "0" || mydigit > "9"){
The || in the if statement scans for both conditions.
The next line will alert the user to any mistakes he/she has made:
alert(mydigit + " is not a number.")
Here is the complete code including HTML:
=============================================
Numerical Validation
| | |
|
| | |