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I'm kind of new to JavaScript and jQuery and now I'm facing a problem:

I'm writing a JSON service in C# (.ashx file). On a successful request to the service I return some JSON data. If the request fails, either because an exception was thrown (e.g. database timeout) or because the request was wrong in some way (e.g. an ID that doesn't exist in the database was given as an argument) how should the service respond? What HTTP status codes are sensible, and should I return any data, if any?

I am designing a web page. In that, when we click the content of div named mail, how can I show a popup window containing a label email and text box?

What does '$' - sign in JQuery stand for?

I have a div (let's say the id is "container") with many elements in it, including a select element. I'd like to select all everything in the div except the select. Things I've tried:

I have a floating div that gets displayed, and I want it to be hidden when the user clicks off the div. This would be similar to the .hover() funtion callback when hovering off an element. Only I want to do this for click.

Looking for a date and datetime picker that will integrate fairly seamlessly with Rails. I'm sure some people must be using something similar. I have tried

Ok what i'm trying to do is to count all of the elements in the current page with the same class and then i'm going to use it to be added onto a name for a input form. Basically i'm allowing users to click on an and then by doing so add another one for more of the same type of items. But i can't think of a way to count all of these simply with jquery/javascript.

I know that in PHP the only difference between double quotes and single quotes is the interpretation of variable inside a string.

When I want some link to not do anything but only respond to javascript actions what's the best way to avoid the link scrolling to the top edge of the page ?

I'm making a pagination system (sort of like Facebook) where the content loads when the user scrolls to the bottom. I imagine the best way to do that is to find when the user is at the bottom of the page and run an ajax query to load more posts.

There are 1 on 1 live chat. Two solutions: 1) I store every message into database and with jQuery's help I check if there is a new message in database every second. Of course I use cache either. If there is, we give that message.

I would like to provide variable row height depending upon the content size. is it possible in Slickgrid? Can you point me towards any examples.

This is a fairly easy one, but I cant seem to figure it out.

This is a minor issue, but one I find myself running into:

I am using ASP.NET MVC with jquery. I have the following MVC Action that returns a partial page on Success. On Application Error, I am not sure what to send it for correctly handling it at the client side.

In my UI I have an accordian setup that so far functions

In jQuery, I have seen both the following ways of defining a jQuery function:

How do I use jQuery with Dojo toolkit? I've heard of both libraries being used simultaneously, jQuery for DOM-related and Dojo for UI (dijit), but I can't find any tutorials or examples of this. Will I run into any conflicts or issues if I load both libraries?

Should I use a local copy of jquery, or should I link to a copy provided by Google or Microsoft? I'm primarily concerned about speed. I've heard that just pulling content from other domains can have performance advantages related to how browsers limit connections. In particular, has anyone benchmarked the speed and latency of Google vs. Microsoft vs. local?