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Creating a Filtering User Interface With jQuery In a Web Forms Application: Part 1 looked at how to use jQuery in an ASP.NET Web Forms application to build a collapsible filtering user interface. When the page is loaded into the user’s browser the filtering interface is collapsed. Clicking the filtering interface’s title toggles the interface between its collapsed and expanded states. When expanded, a user can interact with the filtering controls – DropDownLists, TextBoxes, CheckBoxes, and so on – to narrow down the results displayed in the report beneath the filtering interface. While the filtering interface created in Part 1 certainly works, the collapsed/expanded state of the interface is not remembered. Consequently, on any postback or anytime a user leaves the page and comes back, the filtering interface returns to its collapsed state, regardless of whether the user had it expanded. The good news is that with a touch of AJAX we can have the collapsed/expanded state of the filtering user interface remembered for the duration of a user’s session. This article explores how to add such functionality. Read on to learn more! If you’ve not yet read Part 1 , please do so before tackling Part 2. Read More >

Query operators are methods that work with a sequence of data and perform some task based on the data. They are created as extension methods on the IEnumerable<T> interface, which is the interface implemented by classes that hold enumerable data. For example, arrays and the classes in the System.Collections and System.Collections.Generic namespaces all implement IEnumerable<T> . In The Ins and Outs of Query Operators we looked at how to create your own query operator that, once created, can be applied to any enumerable object. While it is possible to create your own query operators, the good news is that the .NET Framework already ships with a bevy of useful query operators. These query operators are referred to as the standard query operators and are one of the primary pieces of LINQ. The standard query operators include functionality for aggregating sequences of data, concatenating two sequences, converting sequences from one type to another, and splicing out a particular element from the enumeration. There are also standard query operators for generating new sequences, grouping and joining sequences, ordering the elements in sequences, filtering the data in a sequence, and partitioning the sequence. All together, there are more than 40 standard query operators. This article explores some of the more germane ones, giving examples of the standard query operator in use and examining its underlying source code