TableView - RowFilter

[aaronhudon]

Does the TableView support the DataTable's underlying RowFilter?

[tznind]

RowFilter is part of DefaultView which is not used by TableView. However you can generate a new table from the view (see code below for example). If you have a very large table though you may not want to do this on every keystroke. If you apply this filter using background threads or async make sure to update the table using Application.MainLoop.Invoke to prevent changing the table during drawing. Also when you activate or right click etc the cells in the filtered table then the indexes will refer to what is currently displayed (not your original table e.g. dt).

Also you will want some try/catch logic when setting RowFilter because it gives exceptions on bad syntax which would go badly for you if unhandled in a TextChanged callback.

var find = new TextField{Width = 10};
find.TextChanged += (_)=>
{
    if(find.Text.Length == 0)
    {
        dt.DefaultView.RowFilter = null;
    }
    else
    {    
        dt.DefaultView.RowFilter = "There like '%" + find.Text.ToString() +"%'";
    }
    tv.Table = dt.DefaultView.ToTable();
    tv.Update();
};

win.Add(find);

[aaronhudon]

Thanks for the reply - too bad it does not support the DefaultView - my use case is thousands of rows.

[tznind]

Sorry, I should clarify my point on performance.

TableView is designed to support millions of rows and hundreds of columns so may still be a good option for you. Basically if System.Data.DataTable can handle it then TableView can. For example rendering is done starting from the table cell scroll offsets (row/col) and fills the available console screen space (so its super fast and not affected by data volume).

Any performance issues with the above code would be in the allocations of System.Data.DataTable and the ToTable method.

From an architecture point of view, you may want to apply filtering when you query your data source rather than into the UI element. e.g. when user changes filter then send a new query to data source and update table with the results. This moves processing to the server, reduces the amount of records held locally and typically would give you way more control over the filtering than RowFilter alone.