The BaseDataListDesigner.OnPropertyBuilder(object, EventArgs) method invokes a component editor for the associated control that is derived from the System.Web.UI.WebControls.BaseDataList class. It creates a System.Web.UI.Design.WebControls.DataGridComponentEditor or System.Web.UI.Design.WebControls.DataListComponentEditor object, and then invokes the BaseDataListComponentEditor.EditComponent(System.ComponentModel.ITypeDescriptorContext, object, System.Windows.Forms.IWin32Window) method of the component editor.