Below code needs to be corrected for ASP.NET Core Grid Popup Editing :
https://demos.telerik.com/aspnet-core/grid/editing-popup?autoRun=true&theme=default-main-dark
.DataSource(dataSource => dataSource .Ajax() .PageSize(20) .Events(events => events.Error("error_handler")) .Model(model => model.Id(p => p.ProductID)) .Create(update => update.Action("EditingPopup_Create", "Grid")) .Read(read => read.Action("EditingPopup_Read", "Grid")) .Update(update => update.Action("EditingPopup_Update", "Grid")) .Destroy(update => update.Action("EditingPopup_Destroy", "Grid"))
It seems create arrow function is called for update & destroy as well.
while editing the row data EditingPopup_Create create is called instead of update !!