Convert DataRowCollection to IEnumerable <T>

Question

I would like to do something similar in .NET 3.5. What is the fastest way?

IEnumerable<DataRow> collection = TypedDataSet.TypedTableBase<DataRow>.Rows as IEnumerable<DataRow>; 

Answer 1

Assuming you are using .NET 4.0, which introduces covariance:

 // Presumably your table is of some type deriving from TypedTableBase<T>, // where T is an auto-generated type deriving from DataRow. IEnumerable<DataRow> collection = myTypedTable; 

The table type itself implements IEnumerable<T> where T : DataRow .

Otherwise:

 IEnumerable<DataRow> collection = myTypedTable.Cast<DataRow>(); 

Answer 2

You can call OfType<DataRow>() on the DataRowCollection .

Answer 3

A simple direct solution is to use the "Select ()" method of the System.Data.DataTable object that creates the "DataRow []". From this, you can treat it as IEnumberable using Linq, as shown below:

 List<MyItem> items = dtItems.Select().Select(row => new MyItem(row)).ToList(); 

Providing a useful list of objects for each row.

Answer 4

There is a built-in extension method if you add System.Data.DataSetExtensions.dll to your project, which adds the AsEnumerable() method.

 IEnumerable<DataRow> collection = TypedDataSet.TypedTableBase<DataRow>.AsEnumerable();