/// <summary>
/// Specifies a custom fallback to be used if the value of a cell cannot be mapped.
/// </summary>
/// <typeparam name="TPropertyMap">The type of the property map.</typeparam>
/// <param name="propertyMap">The property map to use.</param>
/// <param name="fallbackItem">The fallback to be used if the value of a cell cannot be mapped.</param>
/// <returns>The property map on which this method was invoked.</returns>
public static TPropertyMap WithInvalidFallbackItem <TPropertyMap>(this TPropertyMap propertyMap, IFallbackItem fallbackItem) where TPropertyMap : ISinglePropertyMap
{
propertyMap.InvalidFallback = fallbackItem ?? throw new ArgumentNullException(nameof(fallbackItem));
return(propertyMap);
}
private static bool AutoMap(this Type memberType, FallbackStrategy emptyValueStrategy, out ICellValueMapper mapper, out IFallbackItem emptyFallback, out IFallbackItem invalidFallback)
{
Type type = memberType.GetNullableTypeOrThis(out bool isNullable);
Type[] interfaces = type.GetTypeInfo().ImplementedInterfaces.ToArray();
IFallbackItem ReconcileFallback(FallbackStrategy strategyToPursue, bool empty)
{
// Empty nullable values should be set to null.
if (empty && isNullable)
{
return(new FixedValueFallback(null));
}
else if (strategyToPursue == FallbackStrategy.SetToDefaultValue || emptyValueStrategy == FallbackStrategy.SetToDefaultValue)
{
return(new FixedValueFallback(type.DefaultValue()));
}
else
{
Debug.Assert(emptyValueStrategy == FallbackStrategy.ThrowIfPrimitive);
// The user specified that we should set to the default value if it was empty.
return(new ThrowFallback());
}
}
if (type == typeof(DateTime))
{
mapper = new DateTimeMapper();
emptyFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: false);
}
else if (type == typeof(bool))
{
mapper = new BoolMapper();
emptyFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: false);
}
else if (type.GetTypeInfo().IsEnum)
{
mapper = new EnumMapper(type);
emptyFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: false);
}
else if (type == typeof(string) || type == typeof(object) || type == typeof(IConvertible))
{
mapper = new StringMapper();
emptyFallback = ReconcileFallback(FallbackStrategy.SetToDefaultValue, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.SetToDefaultValue, empty: false);
}
else if (type == typeof(Uri))
{
mapper = new UriMapper();
emptyFallback = ReconcileFallback(FallbackStrategy.SetToDefaultValue, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: false);
}
else if (interfaces.Any(t => t == typeof(IConvertible)))
{
mapper = new ChangeTypeMapper(type);
emptyFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: true);
invalidFallback = ReconcileFallback(FallbackStrategy.ThrowIfPrimitive, empty: false);
}
else
{
mapper = null;
emptyFallback = null;
invalidFallback = null;
return(false);
}
return(true);
}
/// <summary>
/// Specifies a custom fallback to be used if the value of a cell is empty.
/// </summary>
/// <typeparam name="TPropertyMap">The type of the property map.</typeparam>
/// <param name="propertyMap">The property map to use.</param>
/// <param name="fallbackItem">The fallback to be used if the value of a cell is empty.</param>
/// <returns>The property map on which this method was invoked.</returns>
public static TPropertyMap WithEmptyFallbackItem <TPropertyMap>(this TPropertyMap propertyMap, IFallbackItem fallbackItem) where TPropertyMap : IValuePipeline
{
propertyMap.EmptyFallback = fallbackItem ?? throw new ArgumentNullException(nameof(fallbackItem));
return(propertyMap);
}
