Winforms datagridview rowvalidating
The sizing mode for a column is actually determined by its Inherited Auto Size Mode property.
To configure the sizing mode for headers and rows and for columns that do not override the control value, set one or more of the following Data Grid View properties: To override the control's column sizing mode for an individual column, set its Auto Size Mode property to a value other than Not Set.
Because Not Set restores the value inheritance, the Resizable property will never return a Not Set value unless the row or column has not been added to a Data Grid View control.
Set Resizable to Not Set to restore the inheritance.
If the State value includes the Resizable Set flag, the Resizable property value is not inherited.
If you need to determine whether the Resizable property value of a row or column is inherited, examine its State property.
Column fill mode causes the visible columns in the control to fill the width of the control's display area.
28 5.2.2 Row Pre Paint and Post Paint 29 5.3 Autosizing. 33 5.3.5 Customizing Content-based Sizing Behavior. By default, the Resizable property value is based on the Allow User To Resize Columns property value for columns and the Allow User To Resize Rows property value for rows. If content-based automatic sizing is enabled for one dimension only—that is, for rows but not columns, or for columns but not rows—and Wrap Mode is also enabled, size adjustment also occurs whenever the other dimension changes. In this case, call the Update Cell Value method to force the control to update the cell display and apply the current automatic sizing modes. You can customize sizing behaviors when working with derived Data Grid View cell, row, and column types by overriding the Data Grid View Cell. The protected resizing method overloads are designed to work in pairs to achieve an ideal cell height-to-width ratio, avoiding overly wide or tall cells. For example, you might programmatically resize all columns immediately after loading data, or you might programmatically resize a specific row after a particular cell value has been modified. Get Preferred Width() methods or by calling protected resizing method overloads in a derived Data Grid View control.