Update DataTablesFiltering.cs

Fixed an issue when filtering on a data table throws an exception in cases there are no relevant columns to be filtered. Example: data table contains only numerical columns and a user types 'a letter'. Since the letter cannot be converted to a number, no where clause is generated and data.Where command was failing.

Author: jandic

Mvc.JQuery.DataTables.Common/DataTablesFiltering.cs

@@ -30,7 +30,11 @@ public IQueryable<T> ApplyFiltersAndSort<T>(DataTablesParam dtParameters, IQuery
                     }
                 }
                 var values = parts.Where(p => p != null);
-                data = data.Where(string.Join(" or ", values), parameters.ToArray());
+                var filterClause = string.Join(" or ", values);
+                if (string.IsNullOrWhiteSpace(filterClause) == false)
+                {
+                    data = data.Where(filterClause, parameters.ToArray());
+                }
             }
             for (int i = 0; i < dtParameters.sSearchValues.Count; i++)
             {