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 ones that are not.

EDIT 2: Integer.TryParse cannot be use because it cannot be translate to SQL.

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.