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In most usage scenarios, the data displayed in a Microsoft Chart control comes from some dynamic source, such as from a database query. The appearance of the chart can be modified dynamically, as well; past installments in this article series showed how to programmatically customize the axes, labels, and other appearance-related settings. However, it is possible to statically define the chart’s data and appearance strictly through the control’s declarative markup. One of the demos examined in the Getting Started article rendered a column chart with seven columns whose labels and values were defined statically in the <asp:Series> tag’s <Points> collection. Given this functionality, it should come as no surprise that the Microsoft Chart Controls also support serialization . Serialization is the process of persisting the state of a control or an object to some other medium, such as to disk. Deserialization is the inverse process, and involves taking the persisted data and recreating the control or object. With just a few lines of code you can persist the appearance settings, the data, or both to a file on disk or to any stream. Likewise, it takes just a few lines of codes to reconstitute a chart from the persisted information.

The .NET Framework is big. Really big. The System.Web assembly, which contains the guts of ASP.NET, is comprised of nearly 2,000 types, over 23,000 methods, and more than 12,500 properties. And that’s not counting any of the functionality added to ASP.NET since version 2.0. ASP.NET AJAX, the ListView control, Dynamic Data, URL routing, and other features add hundreds of new types and thousands of new methods and properties.

Partial classes and partial methods are two programming language features of .NET programming languages that make it possible for developers to extend and enhance auto-generated code. In a nutshell, partial classes allow for a single class’s members to be divided among multiple source code files. At compile-time these multiple files get combined into a single class as if the class’s members had all been specified in a single file. Partial methods are methods defined in a partial class that are (optionally) divided across two files. With partial methods one file contains the method signature – the method name, its return type, and its input parameters – while the body is (optionally) defined in a separate file. If the partial method’s body is not defined then the compiler automatically removes the partial method signature and all calls to the method at compile-time. Partial classes and partial methods are most commonly used in auto-generated code. The framework or tool that is auto-generating the code can create the auto-generated classes as partial classes. If the developer using the auto-generated code wants to extend the functionality of the class by adding new methods or properties she can do so by creating a new partial class file and putting her additions there. By having these additions in a separate file there’s no risk of the tool overwriting the developer’s changes when regenerating the code. Regardless of whether you know the ins and outs of partial classes you use them every time you create an ASP.NET web page using a code-behind class. And if you routinely use auto-generated libraries, like LINQ to SQL or Typed DataSets, then it behooves you to be familiar with both partial classes and partial methods, as they offer opportunities for safely extending the functionality of auto-generated code. Read on to learn more about how these features work and how you can put them to work

The ASP.NET Toolbox includes two Web controls for managing users’ passwords: the ChangePassword control and the PasswordRecovery control. The ChangePassword control allows a user signed into the site to change their password by entering their existing password and their new, desired password. The PasswordRecovery control is used to reset or recover a user’s password in the event that it has been forgotten. The PasswordRecovery control is used by anonymous users who need to be reminded of their password. Assuming that the Membership system is configured to require that users have a security question and answer (the default behavior), the user is presented with their security question and must correctly enter their security answer in order to have their password reset or recovered. While there are two controls for managing passwords, there are no Web controls in the Toolbox for managing a user’s security question and answer. In other words, there’s no built-in control that allows a signed in user to change her security question and answer. The good news is that while no control offers this functionality it’s not difficult to implement this feature ourselves. The MembershipUser class has a ChangePasswordQuestionAndAnswer method that modifies the security question and answer information using the configured Membership provider. This article shows how to build a page that permits a signed in user to change their security question and answer, and a demo application is available for download at the end of the article that showcases this functionality in action. Read on to learn more! Read More >

Developers using Microsoft’s ASP.NET AJAX framework can efficiently and interactively retrieve data from the web server using the ASP.NET AJAX client API, a bit of JavaScript, and Web services that support script access. Last week’s article, Building Interactive User Interfaces with Microsoft ASP.NET AJAX: Retrieving Server-Side Data Using Web Services , looked at how to create such Web services and how to call them from an ASP.NET AJAX application. With a sprinkle of JavaScript, This functionality can be implemented to provide a user interface that periodically updates, presenting pertinent information to the user without the need for the user to refresh her browser. Consider the following scenario: you are building a website that serves as a front-end for a work item database. The database contains tasks assigned to an employee; throughout the course of the day new tasks may be assigned to an employee by other workers, by automated processes, or by other means. When an employee logs onto the site he sees a hyperlink that lists the number of open work items in the upper left corner of every page, and clicking that link takes him to a page that lists the open work items in his queue. After completing a work item he closes it, which removes it from his list of open work items. In a typical web application the number of open work items in the upper left corner would only be refreshed when the user performed a postback, manually refreshed the page, or visited a new page. Wouldn’t it be nice if that count of open work items would interactively update as new work items assigned to the user entered the queue? This article looks at how to build such an interactive user interface by using the ASP.NET AJAX framework, script-enabled Web services, and a few lines of JavaScript, building upon the techniques discussed in Retrieving Server-Side Data Using Web Services . A complete, working demo is available for download at the end of this article. Read on to learn more! Read More >