DataGridViewCellCollection.Insert Method (Int32, DataGridViewCell)
Inserts a cell into the collection at the specified index.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Use this method to alter the collection before you add the containing row to a DataGridView control. Once you add the row to a control, the number of cells it contains always matches the number of columns in the control, so this method is no longer useful.
Available since 2.0