/// <summary>
/// Gets the foreign key for the given properties that points to a given primary or alternate key. Returns null
/// if no foreign key is found.
/// </summary>
/// <param name="entityType"> The entity type to find the foreign keys on. </param>
/// <param name="property"> The property that the foreign key is defined on. </param>
/// <param name="principalKey"> The primary or alternate key that is referenced. </param>
/// <param name="principalEntityType">
/// The entity type that the relationship targets. This may be different from the type that <paramref name="principalKey" />
/// is defined on when the relationship targets a derived type in an inheritance hierarchy (since the key is defined on the
/// base type of the hierarchy).
/// </param>
/// <returns> The foreign key, or null if none is defined. </returns>
public static IForeignKey FindForeignKey(
[NotNull] this IEntityType entityType,
[NotNull] IProperty property,
[NotNull] IKey principalKey,
[NotNull] IEntityType principalEntityType)
{
Check.NotNull(entityType, nameof(entityType));
return(entityType.FindForeignKey(new[] { property }, principalKey, principalEntityType));
}
public static IForeignKey GetForeignKey([NotNull] this IEntityType entityType, [NotNull] IReadOnlyList <IProperty> properties)
{
var foreignKey = entityType.FindForeignKey(properties);
if (foreignKey == null)
{
throw new ModelItemNotFoundException(Strings.ForeignKeyNotFound(Property.Format(properties), entityType.Name));
}
return(foreignKey);
}