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File Dialog Filter Builder

, 31 Jul 2007 CPOL
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Helper class for building filter string for Windows file dialogs


The Windows file dialogs provide the Filter property to specify which kinds of files should be shown in the dialog. The syntax is pretty simple, but there is still scope to make a mistake and "create" a bug (with typo for example).

Using the Code

The FileDialogFilterBuilder class uses the FilterInfo structure for every filter item. The FilterInfo structure contains all information about one filter item. Using these two types are pretty simple and intuitive:

// Create builder
FileDialogFilterBuilder filterBuilder = new FileDialogFilterBuilder();
// add filter item for Word documents
filterBuilder.Infos.Add( new FilterInfo( "Word", "doc", "docx", "rtf" ) );
// add filter item for Excel documents
filterBuilder.Infos.Add( new FilterInfo( "Excel", "xls", "xlsx", "csv" ) );

// create filter item for images
FilterInfo infoImages = new FilterInfo( "Images" );
// these extensions will be used by dialog for filtering files
infoImages.Extensions = new string[] 
	{ "bmp", "jpg", "gif", "jpeg", "png", "wmf", "emf", "ico" };
// these extensions will be displayed to user with item
infoImages.VisibleExtensions = new string[] { "bmp", "jpg", "gif" };
// add item to builder
filterBuilder.Infos.Add( infoImages );

// add item with no-filter, with title "All file types"
filterBuilder.AddAllFileTypes( "All file types" );

using ( OpenFileDialog ofd = new OpenFileDialog() ) {
    // method "ToFilterString()" builds the filter string with correct syntax
    ofd.Filter = filterBuilder.ToFilterString();
    ofd.ShowDialog( this );

That's all.


  • 1st August, 2007: Initial post


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Jakub Mller
Web Developer
Czech Republic Czech Republic
No Biography provided

Comments and Discussions

GeneralOrdering and Default PinmemberMember 334239818-Aug-09 13:25 
GeneralSystem extension description PinmemberChris Richner1-Aug-07 3:06 
GeneralRe: System extension description PinmemberJakub Müller1-Aug-07 3:44 
AnswerRe: System extension description PinmemberChris Richner1-Aug-07 13:26 
GeneralRe: System extension description PinmemberAnt210027-Oct-09 10:46 
Generalspelling mistake PinmemberMichael Sync31-Jul-07 23:27 
GeneralRe: spelling mistake PinmemberJakub Müller31-Jul-07 23:45 

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