How to Achieve Keyboard Navigation in RadGridView

Environment

Product Version	Product	Author
2021.3.914	RadGridView for WinForms	Desislava Yordanova

Description

A common requirement is to move to a specific row in a RadGridView by typing first letters of where you want to move (e.g. within the selected column). For example, select column Description and type "L". The expected behavior is to move to the first description which begins with a "L", if the user types "LE", move to the first description which begins with "LE", and so on.

This type of functionality is not supported out of the box. However, this article demonstrates a sample approach how to accomplish it.

Solution

Such kind of behavior can be achieved by using a custom row behavior.

• C#
• VB.NET

private void RadForm1_Load(object sender, EventArgs e)
{ 
    this.productsTableAdapter.Fill(this.nwindDataSet.Products);
    this.radGridView1.BestFitColumns();

    // register the custom row  behavior
    BaseGridBehavior gridBehavior = radGridView1.GridBehavior as BaseGridBehavior;
    gridBehavior.UnregisterBehavior(typeof(GridViewDataRowInfo));
    gridBehavior.RegisterBehavior(typeof(GridViewDataRowInfo), new CustomGridDataRowBehavior());

    this.radGridView1.SelectionMode = GridViewSelectionMode.CellSelect;
    this.radGridView1.BeginEditMode = Telerik.WinControls.RadGridViewBeginEditMode.BeginEditProgrammatically;
}

public class CustomGridDataRowBehavior : GridDataRowBehavior
{
    private Timer timer = new Timer();
    private string searchPattern = string.Empty;
    protected override bool ProcessAlphaNumericKey(KeyPressEventArgs keys)
    {
        if (!timer.Enabled)
        {
            timer.Interval = 1000;
            searchPattern = string.Empty;
            timer.Tick -= timer_Tick;
            timer.Tick += timer_Tick;
            timer.Start();
        }
        searchPattern = searchPattern + keys.KeyChar;
        Console.WriteLine(searchPattern);

        return base.ProcessAlphaNumericKey(keys);
    }

    private void timer_Tick(object sender, EventArgs e)
    {
        if (this.GridControl.CurrentColumn != null)
        {
            int startIndex = this.GridControl.CurrentRow.Index;
            for (var index = startIndex + 1; index <= this.GridControl.Rows.Count - 1; index++)
            {
                if ((this.GridControl.Rows[index].Cells[this.GridControl.CurrentColumn.Name].Value +
                    "").ToString().ToLower().StartsWith(searchPattern.ToLower()))
                {
                    this.GridControl.CurrentRow = this.GridControl.Rows[index];
                    break;
                }
            }
        }
        timer.Stop();
    }
}

Private Sub RadForm1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.ProductsTableAdapter.Fill(Me.NwindDataSet.Products)
    Me.RadGridView1.BestFitColumns()

    'register the custom row  behavior
    Dim gridBehavior As BaseGridBehavior = TryCast(RadGridView1.GridBehavior, BaseGridBehavior)
    gridBehavior.UnregisterBehavior(GetType(GridViewDataRowInfo))
    gridBehavior.RegisterBehavior(GetType(GridViewDataRowInfo), New CustomGridDataRowBehavior())

    Me.RadGridView1.SelectionMode = GridViewSelectionMode.CellSelect
    Me.RadGridView1.BeginEditMode = Telerik.WinControls.RadGridViewBeginEditMode.BeginEditProgrammatically
End Sub

Public Class CustomGridDataRowBehavior
    Inherits GridDataRowBehavior
    Dim timer As New Timer
    Dim searchPattern As String = String.Empty
    Protected Overrides Function ProcessAlphaNumericKey(keys As KeyPressEventArgs) As Boolean
        If Not timer.Enabled Then
            timer.Interval = 1000
            searchPattern = String.Empty
            RemoveHandler timer.Tick, AddressOf timer_Tick
            AddHandler timer.Tick, AddressOf timer_Tick
            timer.Start()
        End If
        searchPattern = searchPattern & keys.KeyChar
        Console.WriteLine(searchPattern)

        Return MyBase.ProcessAlphaNumericKey(keys)
    End Function

    Private Sub timer_Tick(sender As Object, e As EventArgs)
        If Me.GridControl.CurrentColumn IsNot Nothing Then
            Dim startIndex As Integer = Me.GridControl.CurrentRow.Index
            For index = startIndex + 1 To Me.GridControl.Rows.Count - 1
                If (Me.GridControl.Rows(index).Cells(Me.GridControl.CurrentColumn.Name).Value & "").ToString().ToLower().StartsWith(searchPattern.ToLower()) Then
                    Me.GridControl.CurrentRow = Me.GridControl.Rows(index)
                    Exit For
                End If 
            Next
        End If
        timer.Stop()
    End Sub

End Class