Performing Advanced Filtering

Performing Advanced Filtering The RowFilter property of a DataView is similar to a WHERE clause in a SELECT statement. You can therefore use very powerful filter expressions in your DataView.
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Performing Advanced FilteringPerforming Advanced FilteringThe RowFilter property of a DataView is similar to a WHERE clause in a SELECTstatement. You can therefore use very powerful filter expressions in your DataView. Forexample, you can use AND, OR, NOT, IN, LIKE, comparison operators, arithmeticoperators, wildcard characters (* and %), and aggregate functions.Note For full details on how to use such filter expressions in your DataView objects, refer to the DataColumn .Expression property in the .NET online documentation.Heres a simple example that uses the LIKE operator and the percent (%) wildcardcharacter to filter rows with a CustomerName that starts with Fr:string filterExpression = CompanyName LIKE Fr%;customersDV.RowFilter = filterExpression;Notice that the string Fr% is placed in single quotes-which you must do for all stringliterals. When this code replaces the existing code in the UsingDataView.cs programshown earlier in Listing 13.1, the output is as follows:FRANKFrankenversandGermanyFRANRFrance restaurationFranceFRANSFranchi S.p.A.ItalyNote Ive made this change in the UsingDataView2.cs program (the listing is omitted from this book for brevity). Feel free to examine and run this program.