How to know if a field is numeric in Linq To SQL

Question

I need to select the rows of a table where a column value is numeric, any Help?

EDIT: I have a varchar column and I need to select the ones that are numbers and the

Answer 1

I don't know if there is a mapping for int.TryParse() in LinqToSQL, but you could probably do it in two steps by performing the query, casting to a List, then selecting out of the list with LinqToObjects.

int i;
var query = context.Table.ToList();
var intQuery = query.Where( t => int.TryParse( t.Column, out i ) );

You might want to look at Dynamic LINQ, too. That would allow you to do something like:

var query = context.Table.Where( "IsNumeric(Column)" );

EDIT Dynamic LINQ is available in the VS2008 Code Samples, linked to from Scott Guthrie's blog, which I've linked above.