Posted in C# on October 20, 2009 | 5 Comments »
Hi All,
I recently received a review about MyCaptcha control in CodePlex that proposed a couple of improvements in the source code. This review indicates that :
Thread.Sleep is not a good way to ensure that unique characters are selected for teh Captcha text.
Sending the Captcha text to rendering component (.ashx file) is insecure.
Based on the above [...]
Posted in ASP.NET, Architecture, C# on June 9, 2009 | Leave a Comment »
When you design a modular ASP.NET application, soon or later you will need to think about adding extensibility features to your project so that it will be possible to add new modules at runtime. There are a few architectures and designs that let you develop an extensible application, like ASP.NET MVP. However, many of them [...]
Posted in ASP.NET, C#, tagged ashx, ASP.NET, C#, captcha, Control, generic handler, graphics, image, scrambled, text on April 9, 2009 | 2 Comments »
In this post I will explain how to generate a hard-to-read image out of our Captcha text. The new Captcha with image will look like this:
In MyCaptcha control, each letter is different from other ones in three properties:
1- Font
2- Size
3- Distance from the next letter (character spacing)
Therefore, I wrote a class named Letter [...]
Posted in ASP.NET, C#, tagged ASP.NET, C#, captcha, Control, free, Source on April 9, 2009 | Leave a Comment »
In this post and a post after I will explain how to develop a Captcha control and use it in an ASP.NET web site.
As described in Wikipedia, A CAPTCHA or Captcha (IPA: /ˈkæptʃə/) is a type of challenge-response test used in computing to ensure that the response is not generated by a computer. [...]
Posted in ADO.NET, ASP.NET, C#, SQL SERVER, tagged ASP.NET, bind, Byte, C#, database, DataReader, DB, express, FILE, from, image, ImageUrl, Load, picture, read, Save, SQL, SQL SERVER, stream, System.Drawing, System.Web, System.Web.UI, System.Web.UI.WebControls, to, url, write on October 17, 2008 | 6 Comments »
Hi,
This post will show you how to save/load images to/from a database. This approach lets you do it without having to save the image on to disk. On a real hosting computer, you probably will not have write permissions. Therefore, it is sometimes vital to do image saving/loading on the fly.
In this post we will [...]
Posted in ASP.NET, C#, tagged 43, asp.ent, C#, Dtabase, get, google, microsoft, microsoft.com, port, post, Query, server, tcp/ip, web service, webservice, Whois on October 13, 2008 | Leave a Comment »
A while back I was involved in developing a web site for a Domain and Hosting reseller. In that project I needed to create a “Find A Domain” section in which the customer could check to see if a domain name exists.
I made a exhaustive research and figured out that each Who is server maintains [...]
Posted in ASP.NET, C#, tagged .net, 3.5, ASP.NET, get, httpwebrequest, Linq, Load, post, rest, Save, service, StreamWriter, web, web service, webrequest, xelement, xml on October 10, 2008 | 2 Comments »
At the time of writing this post, .NET has no specific facility to work with REST services. Though, some services over the web provide information in REST format. For example, http://www.geonames.org (that provides gegraphic information) has a lot of free web services to get geographical information. The other day, I needed to use these services [...]
Posted in ASP.NET, C#, tagged C#, fetch, Linq, LinqDataSource, LinqDataSourceView, Method, on demand, programatically, Select on September 28, 2008 | 5 Comments »
As I mentioned in the previous post, with Insert, Update and Delete methods but without a Select method, LinqDataSource control looks just like a chair with only three legs! Specially when it comes to situations that you have to retrieve records programatically.
I probed alot to see if there is a work around for this problem [...]
