One of the first things shown to me when I started working in my company was Microsoft’s Data Access Application Block. One thing that bothered me was that I constantly had to convert DataSets it returned to strongly typed DataSets used in our programs, which usually meant merging the returned data set with a newly created DataTable. To relieve myself of those repeating tedious 6 lines of code, I made this little class that converts untyped DataSets and DataTables to a strongly typed DataTable.
In a first attempt to solve this problem, I used reflation to create an instance of the typed DataTable, so I had to pass the method the type of the DataTable, and cast it back to itself.
This is a more elegant solution, using generics:
/// <summary>
/// Helper methods and functions.
/// </summary>
/// <typeparam name="T">A strongly type DataTable.
/// A DataTable of type T will be returned from the DataSet.
/// </typeparam>
public static class DataSetAdapter<T>
where T : DataTable, new()
{
/// <summary>
/// Convert the first DataTable from a DataSet to a
/// strongly-typed data table.
/// </summary>
public static T convert(DataSet dataSet)
{
if (dataSet == null)
return null;
if (dataSet.Tables.Count == 0)
return null;
DataTable dataTable = dataSet.Tables[0];
return convert(dataTable);
}
/// <summary>
/// Convert an ordinary DataTable to a strongly-typed
/// data table.
/// </summary>
public static T convert(DataTable dataTable)
{
if (dataTable == null)
return null;
T stronglyTyped = new T();
// add data from the regular DataTable to the
// strongly typed DataTable.
stronglyTyped.Merge(dataTable);
return stronglyTyped;
}
}
The use of the class if pretty straightforward, just pass the DataSet and the Type:
DataSet employeesDataSet = OracleHelper.ExecuteDataset( connectionString, storedProcedure, parameters); EmployeesDataTable employees = DataSetAdapter<EmployeesDataTable>.convert(employeesDataSet);
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