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:

var results = from myRow in myDataTable where results.Field("RowNo") == 1 select results; 

This is not allowed. How do I get something like this working?

I'm amazed that LINQ queries are not allowed on DataTables!

Answer 1

You can't query against the DataTable's Rows collection, since DataRowCollection doesn't implement IEnumerable<T>. You need to use the AsEnumerable() extension for DataTable. Like so:

var results = from myRow in myDataTable.AsEnumerable() where myRow.Field<int>("RowNo") == 1 select myRow; 

And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions

AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the CopyToDataTable() extension.

Below is query with Lambda Expression,

var result = myDataTable     .AsEnumerable()     .Where(myRow => myRow.Field<int>("RowNo") == 1);