public ObjectTableDataLoader(TableDescription description, ObjectDataTable <T> table)
{
if (description == null)
{
throw new ArgumentNullException(nameof(description));
}
if (table == null)
{
throw new ArgumentNullException(nameof(table));
}
this.description = description;
this.table = table;
formatter = new Lazy <Func <T, object[]> >(CreateFormatter);
}
/// <summary>
/// Returns the table specified by name. If a table with the specified name does not already exist, it will be created.
/// </summary>
/// <typeparam name="T">The type of entity that the table should contain.</typeparam>
/// <param name="tableName">
/// Name of the table.
/// <remarks>
/// If this value is null then the name of the entity will be used.
/// </remarks>
/// </param>
/// <returns>The existing table with the specified name, if it exists. Otherwise, a new table will be created.</returns>
/// <exception cref="System.InvalidOperationException">
/// Thrown if the table exists, but the element type specified is incorrect.
/// </exception>
/// <example>
/// <code language="c#">
/// public class Person
/// {
/// public string Name { get; set; }
/// }
/// ...
/// var data = new ObjectData();
/// var table = data.Table<Person>();
/// table.Add(new Person { Name = "Fred" });
/// table.Add(new Person { Name = "Jeff" });
/// foreach (var person in data.Table<Person>())
/// {
/// Debug.Print(person.Name);
/// }
/// // prints:
/// // Fred
/// // Jeff
/// </code>
/// </example>
public ObjectDataTable <T> Table <T>(string tableName = null)
{
tableName = tableName ?? typeof(T).Name;
IEnumerable table;
if (!tables.TryGetValue(tableName, out table) || table == null)
{
table = new ObjectDataTable <T>();
tables[tableName] = table;
}
if (table is ObjectDataTable <T> )
{
return((ObjectDataTable <T>)table);
}
throw new InvalidOperationException($"A table with the name '{tableName}' already exists, but the element type is incorrect.\r\nExpected type: '{typeof(T).Name}'\r\nActual type: '{table.GetType().GetGenericArguments()[0].Name}'");
}