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Google has provided a very reach Google Maps API to use it in our own application. But we need some short of javascript knowledge in order to use it. I don't know about others, but for me it was a little difficult to use javascript along with google apis in ASP.Net pages, specifically if you want to use server side functions to draw google map dynamically. For example, in my case I wanted to pull latitude longitude information from a SQL Server database and then use them to insert pushpins on google map. If you are familiar with Ajax framework, you know the answer. You will have to call asp.net server side function from javascript and use retrieved data to draw a google map. How simple is that? :). Atleast not for me. So I have decided to write a user control which can take care of javascript part and allows me to concentrate on serverside functions.

Chances are, at some point you've tried creating a new user account on a website and were told that the username you selected was already taken. This is especially common on very large websites with millions of members, but can happen on smaller websites with common usernames, such as people's names or popular words or phrases in the lexicon of the online community that frequents the website. If the user registration process is short and sweet, most users won't balk when they are told their desired username has already been taken - they'll just try a new one. But if the user registration process is long, involving several questions and scrolling, it can be frustrating to complete the registration process only to be told you need to return to the top of the page to try a different username.

Many websites use Ajax techniques to check whether a visitor's desired username is available as soon as they enter it (rather than waiting for them to submit the form). This article shows how to implement such a feature in an ASP.NET website using Membership and jQuery. This article includes a demo available for download that implements this behavior in an ASP.NET WebForms application that uses the CreateUserWizard control to register new users. However, the concepts in this article can be applied to ad-hoc user registration pages and ASP.NET MVC.

Read on to learn more!

When building a web application, we must decide how and when the browser will communicate with the web server. The ASP.NET WebForms model greatly simplifies web development by providing a straightforward mechanism for exchanging data between the browser and the server. With WebForms, each ASP.NET page's rendered output includes a <form> element that performs a postback to the same page whenever a Button control within the form is clicked, or whenever the user modifies a control whose AutoPostBack property is set to True. On postback, the server sends the entire contents of the web page back to the browser, which then displays this new content. With WebForms we don't need to spend much time or effort thinking about how or when the browser will communicate with the server or how that returned information will be processed by the browser. It just works.

While this approach certainly works and has its advantages, it's not without its drawbacks. The primary concern with postback forms is that they require a large amount of information to be exchanged between the browser and the server. Specifically, the browser sends back all of its form fields (including hidden ones, like view state, which may be quite large) and then the server sends back the entire contents of the web page. Granted, there are scenarios where this large quantity of data needs to be exchanged, but in many cases we can use techniques that exchange much less information. However, these techniques necessitate spending more time and effort thinking about how and when to have the browser communicate with the server and intelligently deciding on what information needs to be exchanged.

This article, the first in a multi-part series, examines different techniques for accessing server-side data from a browser using client-side script. Throughout this series we will explore alternative ways to expose data on the server so that it can be accessed from the browser using script; we will also examine various tools for communicating with the server from JavaScript, including jQuery and the ASP.NET AJAX library.