/// <summary>
/// Gets the <see cref="MappedType{T}"/> for a specific <see cref="Type"/>
/// that has a mapping registered with a <see cref="ColumnMappingCollection"/>.
/// </summary>
/// <typeparam name="T">
/// The registered <see cref="Type"/> to get the column mappings for.
/// </typeparam>
/// <param name="mappings">
/// The instance of <see cref="ColumnMappingCollection"/> containing the registered instance of
/// <see cref="MappedType{T}"/> associated with the <see cref="Type"/> specified for <typeparamref name="T"/>.
/// </param>
/// <param name="throwIfTypeNotMapped">
/// When set to <c>true</c>, an exception will be thrown if the <see cref="Type"/> specified for
/// <typeparamref name="T"/> has not been registered with the <see cref="ColumnMappingCollection"/>.
/// </param>
/// <returns>
/// The <see cref="MappedType{T}"/> that has been registered with the
/// <see cref="ColumnMappingCollection"/> for the <see cref="Type"/>
/// specified for <typeparamref name="T"/>.
/// </returns>
/// <exception cref="ArgumentNullException">
/// Thrown if the <paramref name="mappings"/> parameter is <c>null</c>.
/// </exception>
/// <exception cref="System.Collections.Generic.KeyNotFoundException">
/// Thrown if the <paramref name="throwIfTypeNotMapped"/> parameter is set to <c>true</c>,
/// and if the <see cref="Type"/> specified for <typeparamref name="T"/> has not been
/// registered with the <see cref="ColumnMappingCollection"/>.
/// </exception>
public static MappedType <T> GetTypeMapping <T>(this ColumnMappingCollection mappings, bool throwIfTypeNotMapped)
{
if (mappings == null)
{
throw new ArgumentNullException(nameof(mappings));
}
if (mappings.TypeHasBeenMapped <T>())
{
return(mappings.Mappings[typeof(T)] as MappedType <T>);
}
if (!throwIfTypeNotMapped)
{
return(null);
}
var message = $"The {typeof(T)} type has not been registered with the {typeof(ColumnMappingCollection).Name}.";
throw new System.Collections.Generic.KeyNotFoundException(message);
}
