https://learn.microsoft.com/ru-ru/dotnet/api/system.windows.forms.datagridview.databindingcomplete?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-9.0
DataGridView.DataBindingComplete Event (System.Windows.Forms) | Microsoft Learn
Occurs after a data-binding operation has finished.
event systemwindows formsdatagridviewmicrosoftlearn