Here is a thread that I had with Component Art support. I have not tested this - I have largely dropped my testing of Linq to sql because of this issue. I have problems with Janus Winform grids also.
Sirs:
I'm trying to start using linq in a web form.
I can't get a grid to bind to a resultset that comes from a stored procedure.
The error that I'm getting is 'Object reference not set to an instance of an object' when databinding.
I see a post that mentions converting the ISINGLERESULT into a Datatable, but can't figure that out.
Can you help?
Hello,
That error isn't what I'd expect to see- are you able to bind this linq query to a standard datagrid?
The error we're aware of is that the grid can't enumerate through a linq data source; thus, something like this:
Grid1.DataSource = from person in people select person; Grid1.DataBind();
Fails with a nullreferenceexception. To workaround that, you could do
this:
var linq = from person in people select person; Grid1.DataSource = linq.ToList(); Grid1.DataBind();
So in your code, set your results to a var type, then cast the type to one the grid can enumerate (a list as above, or a DataTable, etc).
Stephen Hatcher
Developer Support Manager
ComponentArt Inc.
Sirs:
Your examples are using standard linq to sql access, I'm using the *stored
procedure* access.
Scott Gu demonstrates this here
http://weblogs.asp.net/scottgu/archive/2007/08/16/linq-to-sql-part-6-ret
riev
ing-data-using-stored-procedures.aspx
All my data access is via stored procs.
I'd be happy with the '.tolist' approach, but I can't get a stored procedure result to do that. Can you help?
Hello,
I see. Unless I'm mistaken (and I very well could be), this article shows you how to do that. Unfortunately it's all images, but take a look at this one:
http://www.scottgu.com/blogposts/linqsproc1/step12.jpg
You can see him casting his proc to a list there. In a previous example, you can see him set the results of his proc to the var type as well:
http://www.scottgu.com/blogposts/linqsproc1/step6.jpg
So you could use that, then use ToList on the var. Does that make sense?
Stephen Hatcher
Developer Support Manager
ComponentArt Inc.