As you know, the .net DataTime value type has no concept of an empty or null date. Basically, you need to have a convention in your application that some value, usually 1/1/1900 or 1/1/1, will represent an empty date. I think Rick Strahl had some sample code here on the foums a couple of weeks back that showed how to databind to an emtpy date. When you are persisting the value you check for the empty date "value" and write back a System.DBNull to the table.

Ultimately, I believe that the best way to introduce the concept of nullability to value types in .net will be something along the lines of the NullableTypes project (http://nullabletypes.sourceforge.net/).


>In a winform app, I’m using a textbox class derived from mmTextBox bound to a datetime column in MSSQL. How do I make it save a NULL back to the database when the date is removed by the user? Even when the date is set to blank it reverts to the original date.
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>Terry Carroll