DataGridView.AutoResizeRowHeadersWidth Method (DataGridViewRowHeadersWidthSizeMode)
Adjusts the width of the row headers using the specified size mode.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
This method is useful if you want to control when the row headers resize. The width of the row headers is adjusted only once per method call; if the contents of the row headers later change, the row headers will not automatically adjust. To set the row headers to automatically resize when their contents change, use the RowHeadersWidthSizeMode property.
This method lets you specify a sizing mode that calculates the new width based on values in a limited set of headers, such as those in displayed rows only. This improves performance when the control contains a large number of rows.
For more information about programmatic resizing, see Sizing Options in the Windows Forms DataGridView Control.