I currently have a date textbox that has the bindingfield and businessobjectname properties set, and is populating based on that. However, since I am working with dates, I have set a NULL replacement value in the business object mapper of CDate("1/1/1800").

Is this a Winform or a ASP.NET app?  If you are using Winforms, there are SF controls designed to handle dates when using a null replacement value. The DateTimePicker has a NullDateValue property and the DateBox has the EmptyValue property. 

this is an ASP.NET app

Thanks for the reply, Greg, and thanks for tagging it. I see this post is closest to what I am looking to do: http://forum.strataframe.net/Topic13228.aspx

Greg,

You won't be storing 1/1/1800 in the database (or you don't have to), you'll be storing NULL in the database. When you use the BO Mapper to map a datetime field to a column in the database and you use the Null option value of Return Alternate on Null / Set Null on Alternate, this sets the value of the field in the BO to the alternate value (1/1/1800 in this case), but when storing data in the database, if the value in the BO is 1/1/1800, it sends a NULL to the db for storage (See note below).

So, what the post you found (I totally forgot about that one) is saying is that you separate the property you are binding from the property you are displaying. Then you synch the display property and the binding property via events.

Let us know if you run into problems with the sub-classed TextBox.

Details of Alternate Nulls
What is actually happening is that the property in the BO is referencing a column in the underlying DataTable. The property getter checks if the value in the DataTable is DbNull and if it is, it returns the alternate value. In the setter, it checks if the value being set is the alternate value and if it is, it sets the column in the DataTable to DbNull.  Check out the .designer file to see what is actually happening.

Hi Greg,

I use "new DateTime(1800,1,1)" as alternate value in the bo, and it works for me when using SF datetimepicker.

This just so you maybe could narrow your problem down to the subclassed textbox, if it doesn't work.



/Teddy

Teddy right on the money. The web adds some complexity so sometimes it's a good idea to create a mini test project, a SF C# (or VB.NET...whatever you use) Winform app, copy your BO over, and see if it works. If the BO is working, then you have an issue with the TextBox, but likely it is a configuration issue.  I've attached an image showing the settings in the BO mapper.

Oh boy... I feel like an idiot. The problem was that the save() function was being overridden and a stored procedure was taking over. So DUH! I have to pass the DBNull value myself!

LOL, glad you got it figured out!