Datagridview call cellvalidating
Thanks, Depends on what design pattern (if any) you are following.
Technically speaking you should remove your business logic away from your UI layer and have some sort of Validation Object to validate the data in your presentation layer and then post back the results to your view.
You can also handle events that let you maintain values not typically stored in a bound data source, such as cell Tool Tip text, cell and row error text, cell and row shortcut menu data, and row height data.
Now, since so many books use the Cell Validating event, I wonder if there is not any gotcha (in display for example) with using the Cell Value Changed?
I understand that the impact in performance should be irrelevant when using simple validation and conditional highlighting rules but I would as much prefer it not to run useless code everytime the user moves to another cell if it can be avoided.
This is sometimes called "mixed mode" and is useful for displaying things like calculated values or user-interface (UI) controls.
Because unbound columns are outside the data source, they are ignored by the data source's sorting operations. Data Grid View Combo Box Column class reference topics.