Data Access: Sort and Filter with a Dataview
This sample shows some how to use a dataview to sort and filter the contents of
a table of product information.
Featured Highlights:
The code demonstrates how to use a dataview to sort and filter the contents of
the products table from the Northwind SQL Server database. When the main form
loads, the products table is retrived into a dataset using a simple SQL
Select statement. A dataview is constructed to filter and sort the
products table. The user can select filter and sort criteria and view the
results in a datagrid, without having to return to the data source. Rows may be
filtered by selecting those products that have a user selected first character,
for example all product names that begin with C, or by the UnitsInStock column,
for example all rows that have > 10 units. The rows displayed may also be
sorted on a primary/secondary sort key, each sort key allowing ascending or
descending ordering. The primary sort key is the UnitsInStock column and
the secondary key is UnitsOnOrder column.
Requirements:
Trial or Release version of Visual Studio .NET Professional (or greater).
Access to the Northwind database residing in SQL Server or the Microsoft Data
Engine (MSDE). To install MSDE, do the following:
-
Open the Start menu, then click Programs, the click Microsoft
.NET Framework SDK, and then click Samples and Quickstart Tutorials.
-
Click "Step 1: Install the .NET Framework Samples Database".
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Open a command window, and CD to
\Samples\Setup This is typically : C:\Program Files\Microsoft Visual Studio
.NET\FrameworkSDK\Samples\Setup
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Type: osql -E -S (local)\NetSDK -i InstNwnd.sql
Running the Sample
Simply press F5.
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When the main form initially loads a dataset is loaded with all
rows form the products table in the Northwind database. All manipulations
of this product data that subsequently occur are accomplished by filtering/
sorting the disconnected copy of the product data in the dataset through usage
of a dataview. The product data is not retreived from the data source
after the initial load in order to satisfy any user filter/sort requests.
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Filter criteria specifies the subset of rows based on an
expression. Expressions have a very rich syntax which can accommodate
complex selection criteria.
See Also:
System.Data
Namespace,
DataView Class,
Creating a DataView,
Sorting and Filtering Using a DataView