How to check if at least one field is set in a form before submiting using JQuery

I have a form with many fields (Textbox, Listbox, Checkbox, Radio Button, File box, Text Area) in my PHP page. When submitting the form, I need to check at least one field must be set. If it’s not I don’t want to submit the form. The form is having lots of control, so it’s not a good idea to go through each control to check if a value is set. So here is a JavaScript function which will make the job very easy.

Query to find missing Id's in MySQL

SELECT a.id+1 AS start, MIN(b.id) - 1 AS end
FROM testtable AS a, testtable AS b
WHERE a.id < b.id
GROUP BY a.id
HAVING start < MIN(b.id)

Calling Javascript when JQuery UI Tab is selected or clicked

 Recently I had a requirement in one of my project. I am using JQuery UI Tabed view and what I required was to send an Ajax call when a tab is selected. At the start I find it tough to capture onClick or onSelect event of tabs. But later on I got the solution, I would like to share it with all of you. In below given example I put both solutions that I found to capture if a tab is clicked or selected.

Creating a scrollable table with fixed row and column

To create a Scrollable Table you will need to download JQuery library and jquery.fixer plugging from http://plugins.jquery.com/project/fixer

On this page when you click on download link, a zipped folder will get downloaded. Unzip that folder and then copy "jquery.js" and "jquery.fixer.js" files into the folder where your webpage exist.

To create a scrollable table into your webpage, all you need to do is include "jquery.js" and "jquery.fixer.js" files in your webpage and then on document.ready event, for the table on which you want to enable scrolling call fixer function from "jquery.fixer.js" file. For more detail, see the demo code given below.

How to set the focus to a child window without refreshing it?

Recently I had a requirement, in my web page which contain four links, each link open a popup window. I am using a common JavaScript function to open popup window as given below,

Now when click on a link, it opens a popup window, which contain a data entry form, I entered some information into that form. Then I need to review other information, from other popup window, so I go back to the main window, click on another link, a new popup window get open which contain the information I need to review. I get the information and close this popup window, so now I am on the main window, then again I click on the link for that data entry form, so the popup window comes up but I lost the information that I have entered, that's because I am relodiing the popup window once again. So here the question arise,

1. Is their any way, I can check out the if popup window is already open from parent window, without having the object of popup window just by the name?
2. If the popup window is already open how can I just set the focus to it, rather then reloading it?
3. Can I refer a popup window from a parent window, even after refreshing the parent window?

And finally I got the solution for all the questions. Make some changes in the function as given below and it start working the way I want it,
















Let us see how it works,

• When attempt to open the window again with the same name in the second parameter of the windows open method, you will to get the windows handle. If the window is already open, it will return the handle of the opened window or it will open a new window and return it's handle
• The first parameter (the url) is passed as an empty string, so the page will not get redirected which will result in the contents of the window remaining unchanged.

Note : You cannot get the handle if the page is not on the same host as its opener

Add & Remove values to a Multi Select list box using JQuery

This control is used to add value to a multiselect list box. And to remove multiple values fron this list box.


Where this control can be useful?
Consider the requirement for adding attributes along with it values (eg. attribute colour with values like red, green, blue... where the number of attribute values are not fixed). Is's good to use this control for adding multiple attribute value, rather then having a seperate screen to add the values.

JQuery Script to add table row and column dynemically