LINQ query on a DataTable

Question

I\'m trying to perform a LINQ query on a DataTable object and bizarrely I am finding that performing such queries on DataTables is not straightforward. For example:

Answer 1

In my application I found that using LINQ to Datasets with the AsEnumerable() extension for DataTable as suggested in the answer was extremely slow. If you're interested in optimizing for speed, use James Newtonking's Json.Net library (http://james.newtonking.com/json/help/index.html)

// Serialize the DataTable to a json string
string serializedTable = JsonConvert.SerializeObject(myDataTable);    
Jarray dataRows = Jarray.Parse(serializedTable);

// Run the LINQ query
List results = (from row in dataRows
                    where (int) row["ans_key"] == 42
                    select row).ToList();

// If you need the results to be in a DataTable
string jsonResults = JsonConvert.SerializeObject(results);
DataTable resultsTable = JsonConvert.DeserializeObject(jsonResults);