How to insert custom button inside Navigation bar to insert new row to Grid?

You can Insert new row using the Navigation bar with the custom ButtonBarItemType. Please use the below code snippet to achieve this:

C#

   protected void GridGroupingControl1_BarButtonItemClicked(object source, Syncfusion.Web.UI.WebControls.Grid.Grouping.ButtonBarItemClickEventArgs e)

    {

        if (e.ButtonBarItem.Text == "Insert")

        {

this.GridGroupingControl1.TableDescriptor.AllowNew = true;

        }

}

VB

 Protected Sub GridGroupingControl1_BarButtonItemClicked(ByVal source As Object, ByVal e As Syncfusion.Web.UI.WebControls.Grid.Grouping.ButtonBarItemClickEventArgs)

  If e.ButtonBarItem.Text = "Insert" Then

Me.GridGroupingControl1.TableDescriptor.AllowNew = True

  End If

  End Sub

Please refer the sample in the link mentioned below which illustrates the above:

http://websamples.syncfusion.com/samples/Grid.Web/6.1.0.34/42171/main.htm